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Cisco Security Appliance Command Reference, Version 7.2
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About this Guide
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Using the Command Line Interface
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aaa accounting command through accounting-server-group Commands
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acl-netmask-convert through auto-update timeout Commands
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backup interface through browse networks Commands
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cache through clear compression Commands
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clear configure through clear configure vpn-load-balancing Commands
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clear conn through clear xlate Commands
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client-access-rule through crl-configure Commands
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crypto ca authenticate through customization Commands
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ddns through debug xdmcp Commands
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default through duplex Commands
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email through functions Commands
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gateway through hw-module module shutdown Commands
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icmp through imap4s Commands
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inspect ctiqbe through inspect xdmcp Commands
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intercept-dhcp through issuer-name Commands
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java-trustpoint through kill Commands
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l2tp tunnel hello through log-adj-changes Commands
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logging asdm through logout message Commands
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mac-address through multicast-routing Commands
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name through override-account-disable Commands
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packet-tracer through pwd Commands
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queue-limit through router rip Commands
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same-security-traffic through show asdm sessions Commands
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show asp drop through show curpriv Commands
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show ddns through show ipv6 traffic Commands
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show isakmp sa through show route Commands
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show running-config through show running-config isakmp Commands
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show running-config ldap through show running-config webvpn auto-signon Commands
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show service-policy through show xlate Commands
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shun through sysopt radius ignore-secret Commands
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tcp-map through tx-ring-limit Commands
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urgent-flag through write terminal Commands
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Feedback
Table Of Contents
aaa accounting command through accounting-server-group Commands
aaa accounting include, exclude
aaa authentication include, exclude
aaa authentication secure-http-client
aaa local authentication attempts max-fail
accounting-server-group (webvpn)
aaa accounting command through accounting-server-group Commands
aaa accounting command
To send accounting messages to the TACACS+ accounting server when you enter any command other than show commands at the CLI, use the aaa accounting command command in global configuration mode. To disable support for command accounting, use the no form of this command.
aaa accounting command [privilege level] tacacs+-server-tag
no aaa accounting command [privilege level] tacacs+-server-tag
Syntax Description
Defaults
The default privilege level is 0.
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Command History
Usage Guidelines
When you configure the aaa accounting command command, each command other than show commands entered by an administrator is recorded and sent to the accounting server or servers.
Examples
The following example specifies that accounting records will be generated for any supported command, and that these records are sent to the server from the group named adminserver.
hostname(config)# aaa accounting command adminserverRelated Commands
aaa accounting console
To enable support for AAA accounting for administrative access, use the aaa accounting console command in global configuration mode. To disable support for aaa accounting for administrative access, use the no form of this command.
aaa accounting {serial | telnet | ssh | enable} console server-tag
no aaa accounting {serial | telnet | ssh | enable} console server-tag
Syntax Description
Defaults
By default, AAA accounting for administrative access is disabled.
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Command History
Usage Guidelines
You must specify the name of the server group, previously specified in an aaa-server command.
Examples
The following example specifies that accounting records will be generated for all Telnet transactions, and that these records are sent to the server named adminserver.
hostname(config)# aaa accounting telnet console adminserverRelated Commands
aaa accounting include, exclude
To enable accounting for TCP or UDP connections through the security appliance, use the aaa accounting include command in global configuration mode. To exclude addresses from accounting, use the aaa accounting exclude command. To disable accounting, use the no form of this command.
aaa accounting {include | exclude} service interface_name inside_ip inside_mask [outside_ip outside_mask] server_tag
no aaa accounting {include | exclude} service interface_name inside_ip inside_mask [outside_ip outside_mask] server_tag
Syntax Description
Defaults
By default, AAA accounting for administrative access is disabled.
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Command History
Usage Guidelines
The security appliance can send accounting information to a RADIUS or TACACS+ server about any TCP or UDP traffic that passes through the security appliance. If that traffic is also authenticated, then the AAA server can maintain accounting information by username. If the traffic is not authenticated, the AAA server can maintain accounting information by IP address. Accounting information includes when sessions start and stop, username, the number of bytes that pass through the security appliance for the session, the service used, and the duration of each session.
Before you can use this command, you must first designate a AAA server with the aaa-server command.
To enable accounting for traffic that is specified by an access list, use the aaa accounting match command. You cannot use the match command in the same configuration as the include and exclude commands. We suggest that you use the match command instead of the include and exclude commands; the include and exclude commands are not supported by ASDM.
You cannot use the aaa accounting include and exclude commands between same-security interfaces. For that scenario, you must use the aaa accounting match command.
Examples
The following example enables accounting on all TCP connections:
hostname(config)# aaa-server mygroup protocol tacacs+hostname(config)# aaa-server mygroup (inside) host 192.168.10.10 thekey timeout 20hostname(config)# aaa accounting include any inside 0 0 0 0 mygroupRelated Commands
aaa accounting match
To enable accounting for TCP and UDP connections through the security appliance, use the aaa accounting match command in global configuration mode. To disable accounting for traffic, use the no form of this command.
aaa accounting match acl_name interface_name server_tag
no aaa accounting match acl_name interface_name server_tag
Syntax Description
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Command History
Usage Guidelines
The security appliance can send accounting information to a RADIUS or TACACS+ server about any TCP or UDP traffic that passes through the security appliance. If that traffic is also authenticated, then the AAA server can maintain accounting information by username. If the traffic is not authenticated, the AAA server can maintain accounting information by IP address. Accounting information includes when sessions start and stop, username, the number of bytes that pass through the security appliance for the session, the service used, and the duration of each session.
Before you can use this command, you must first designate a AAA server with the aaa-server command.
Accounting information is sent only to the active server in a server group unless you enable simultaneous accounting using the accounting-mode command in aaa-server protocol configuration mode.
You cannot use the aaa accounting match command in the same configuration as the aaa accounting include and exclude commands. We suggest that you use the match command instead of the include and exclude commands; the include and exclude commands are not supported by ASDM.
Examples
The following example enables accounting for traffic matching a specific access list acl2:
hostname(config)# access-list acl12 extended permit tcp any any
hostname(config)# aaa accounting match acl2 outside radserver1Related Commands
aaa authentication include, exclude
To enable authentication for connections through the security appliance, use the aaa authentication include command in global configuration mode. To exclude addresses from authentication, use the aaa authentication exclude command. To disable authentication, use the no form of this command.
aaa authentication {include | exclude} service interface_name inside_ip inside_mask [outside_ip outside_mask] {server_tag | LOCAL}
no aaa authentication {include | exclude} service interface_name inside_ip inside_mask [outside_ip outside_mask] {server_tag | LOCAL}
Syntax Description
exclude
Excludes the specified service and address from authentication if it was already specified by an include command.
include
Specifies the services and IP addresses that require authentication. Traffic that is not specified by an include statement is not processed.
inside_ip
Specifies the IP address on the higher security interface. This address might be the source or the destination address, depending on the interface to which you apply this command. If you apply the command to the lower security interface, then this address is the destination address. If you apply the command to the higher security interface, then this address is the source address. Use 0 to mean all hosts.
inside_mask
Specifies the network mask for the inside IP address. Use 0 if the IP address is 0. Use 255.255.255.255 for a host.
interface_name
Specifies the interface name from which users require authentication.
LOCAL
Specifies the local user database.
outside_ip
(Optional) Specifies the IP address on the lower security interface. This address might be the source or the destination address, depending on the interface to which you apply this command. If you apply the command to the lower security interface, then this address is the source address. If you apply the command to the higher security interface, then this address is the destination address. Use 0 to mean all hosts.
outside_mask
(Optional) Specifies the network mask for the outside IP address. Use 0 if the IP address is 0. Use 255.255.255.255 for a host.
server_tag
Specifies the AAA server group defined by the aaa-server command.
service
Specifies the services that require authentication. You can specify one of the following values:
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Although you can configure the security appliance to require authentication for network access to any protocol or service, users can authenticate directly with HTTP, HTTPS, Telnet, or FTP only. A user must first authenticate with one of these services before the security appliance allows other traffic requiring authentication. See "Usage Guidelines" for more information.
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Command History
Usage Guidelines
To enable authentication for traffic that is specified by an access list, use the aaa authentication match command. You cannot use the match command in the same configuration as the include and exclude commands. We suggest that you use the match command instead of the include and exclude commands; the include and exclude commands are not supported by ASDM.
You cannot use the aaa authentication include and exclude commands between same-security interfaces. For that scenario, you must use the aaa authentication match command.
TCP sessions might have their sequence numbers randomized even if you disable sequence randomization. This occurs when a AAA server proxies the TCP session to authenticate the user before permitting access.
One-Time Authentication
A user at a given IP address only needs to authenticate one time for all rules and types, until the authentication session expires. (See the timeout uauth command for timeout values.) For example, if you configure the security appliance to authenticate Telnet and FTP, and a user first successfully authenticates for Telnet, then as long as the authentication session exists, the user does not also have to authenticate for FTP.
For HTTP or HTTPS authentication, once authenticated, a user never has to reauthenticate, no matter how low the timeout uauth command is set, because the browser caches the string "Basic=Uuhjksdkfhk==" in every subsequent connection to that particular site. This can be cleared only when the user exits all instances of the web browser and restarts. Flushing the cache is of no use.
Applications Required to Receive an Authentication Challenge
Although you can configure the security appliance to require authentication for network access to any protocol or service, users can authenticate directly with HTTP, HTTPS, Telnet, or FTP only. A user must first authenticate with one of these services before the security appliance allows other traffic requiring authentication.
The authentication ports that the security appliance supports for AAA are fixed:
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Security Appliance Authentication Prompts
For Telnet and FTP, the security appliance generates an authentication prompt.
For HTTP, the security appliance uses basic HTTP authentication by default, and provides an authentication prompt. You can optionally configure the security appliance to redirect users to an internal web page where they can enter their username and password (configured with the aaa authentication listener command).
For HTTPS, the security appliance generates a custom login screen. You can optionally configure the security appliance to redirect users to an internal web page where they can enter their username and password (configured with the aaa authentication listener command).
Redirection is an improvement over the basic method because it provides an improved user experience when authenticating, and an identical user experience for HTTP and HTTPS in both Easy VPN and firewall modes. It also supports authenticating directly with the security appliance.
You might want to continue to use basic HTTP authentication if: you do not want the security appliance to open listening ports; if you use NAT on a router and you do not want to create a translation rule for the web page served by the security appliance; basic HTTP authentication might work better with your network. For example non-browser applications, like when a URL is embedded in email, might be more compatible with basic authentication.
After you authenticate correctly, the security appliance redirects you to your original destination. If the destination server also has its own authentication, the user enters another username and password. If you use basic HTTP authentication and need to enter another username and password for the destination server, then you need to configure the virtual http command.
Note
For FTP, a user has the option of entering the security appliance username followed by an at sign (@) and then the FTP username (name1@name2). For the password, the user enters the security appliance password followed by an at sign (@) and then the FTP password (password1@password2). For example, enter the following text.
name> jamiec@jchrichtonpassword> letmein@he110This feature is useful when you have cascaded firewalls that require multiple logins. You can separate several names and passwords by multiple at signs (@).
The number of login attempts allowed differs between the supported protocols:
Static PAT and HTTP
For HTTP authentication, the security appliance checks real ports when static PAT is configured. If it detects traffic destined for real port 80, regardless of the mapped port, the security appliance intercepts the HTTP connection and enforces authentication.
For example, assume that outside TCP port 889 is translated to port 80 (www) and that any relevant access lists permit the traffic:
static (inside,outside) tcp 10.48.66.155 889 192.168.123.10 www netmask 255.255.255.255Then when users try to access 10.48.66.155 on port 889, the security appliance intercepts the traffic and enforces HTTP authentication. Users see the HTTP authentication page in their web browsers before the security appliance allows HTTP connection to complete.
If the local port is different than port 80, as in the following example:
static (inside,outside) tcp 10.48.66.155 889 192.168.123.10 111 netmask 255.255.255.255Then users do not see the authentication page. Instead, the security appliance sends to the web browser an error message indicating that the user must be authenticated prior using the requested service.
Authenticating Directly with the Security Appliance
If you do not want to allow HTTP, HTTPS, Telnet, or FTP through the security appliance but want to authenticate other types of traffic, you can authenticate with the security appliance directly using HTTP or HTTPS by configuring the aaa authentication listener command.
You can authenticate directly with the security appliance at the following URLs when you enable AAA for the interface:
http://interface_ip[:port]/netaccess/connstatus.htmlhttps://interface_ip[:port]/netaccess/connstatus.htmlAlternatively, you can configure virtual Telnet (using the virtual telnet command). With virtual Telnet, the user Telnets to a given IP address configured on the security appliance, and the security appliance provides a Telnet prompt.
Examples
The following example includes for authentication TCP traffic on the outside interface, with an inside IP address of 192.168.0.0 and a netmask of 255.255.0.0, with an outside IP address of all hosts, and using a server group named tacacs+. The second command line excludes Telnet traffic on the outside interface with an inside address of 192.168.38.0, with an outside IP address of all hosts:
hostname(config)# aaa authentication include tcp/0 outside 192.168.0.0 255.255.0.0 0 0 tacacs+hostname(config)# aaa authentication exclude telnet outside 192.168.38.0 255.255.255.0 0 0 tacacs+The following examples demonstrate ways to use the interface-name parameter. The security appliance has an inside network of 192.168.1.0, an outside network of 209.165.201.0 (subnet mask 255.255.255.224), and a perimeter network of 209.165.202.128 (subnet mask 255.255.255.224).
This example enables authentication for connections originated from the inside network to the outside network:
hostname(config)# aaa authentication include tcp/0 inside 192.168.1.0 255.255.255.0 209.165.201.0 255.255.255.224 tacacs+This example enables authentication for connections originated from the inside network to the perimeter network:
hostname(config)#aaa authentication include tcp/0 inside 192.168.1.0 255.255.255.0 209.165.202.128 255.255.255.224 tacacs+This example enables authentication for connections originated from the outside network to the inside network:
hostname(config)# aaa authentication include tcp/0 outside 192.168.1.0 255.255.255.0 209.165.201.0 255.255.255.224 tacacs+This example enables authentication for connections originated from the outside network to the perimeter network:
hostname(config)# aaa authentication include tcp/0 outside 209.165.202.128 255.255.255.224 209.165.201.0 255.255.255.224 tacacs+This example enables authentication for connections originated from the perimeter network to the outside network:
hostname(config)#aaa authentication include tcp/0 perimeter 209.165.202.128 255.255.255.224 209.165.201.0 255.255.255.224 tacacs+Related Commands
aaa authentication console
To enable authentication service for access to the security appliance console over an SSH, HTTP, or Telnet connection or from the Console connector on the security appliance, use the aaa authentication console command in global configuration mode. This command also lets you enable access to privileged EXEC mode. To disable this authentication service, use the no form of this command.
aaa authentication {serial | enable | telnet | ssh | http} console {server-tag [LOCAL] | LOCAL}
no aaa authentication {serial | enable | telnet | ssh | http} console {server-tag [LOCAL] | LOCAL}
Syntax Description
Defaults
By default, fallback to the local database is disabled.
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Command History
Usage Guidelines
If you enable CLI authentication, the security appliance prompts you for your username and password to log in. After you enter your information, you have access to user EXEC mode.
To enter privileged EXEC mode, enter the enable command or the login command (if you are using the local database only).
If you configure enable authentication, the security appliance prompts you for your username and password. If you do not configure enable authentication, enter the system enable password when you enter the enable command (set by the enable password command). However, if you do not use enable authentication, after you enter the enable command, you are no longer logged in as a particular user. To maintain your username, use enable authentication. This feature is particularly useful when you perform command authorization, where usernames are important to determine the commands a user can enter.
For authentication using the local database, you can use the login command, which maintains the username but requires no configuration to turn on authentication.
Before the security appliance can authenticate a Telnet, SSH, or HTTP user, you must first configure access to the security appliance using the telnet, ssh, and http commands. These commands identify the IP addresses that are allowed to communicate with the security appliance. Telnet access to the security appliance console is available from any internal interface, and from the outside interface with IPSec configured. SSH access to the security appliance console is available from any interface.
The http keyword authenticates the ASDM client that accesses the security appliance using HTTPS. You only need to configure HTTP authentication if you want to use a AAA server. By default, ASDM uses the local database for authentication even if you do not configure this command. HTTP management authentication does not support the SDI protocol for a AAA server group.
If you use a AAA server group for authentication, you can configure the security appliance to use the local database as a fallback method if the AAA server is unavailable. Specify the server group name followed by LOCAL (LOCAL is case sensitive). We recommend that you use the same username and password in the local database as the AAA server because the security appliance prompt does not give any indication which method is being used.
You can alternatively use the local database as your main method of authentication (with no fallback) by entering LOCAL alone.
The maximum username prompt for HTTP authentication is 30 characters. The maximum password length is 16 characters.
As the following table shows, the action of the prompts for authenticated access to the security appliance console differ, depending on the option you choose with this command.
If the SSH authentication request times out (which implies the AAA servers may be down or not available), you can gain access to the security appliance using the username pix and the enable password (set with the enable password command). By default, the enable password is blank. This behavior differs from when you log into the security appliance without AAA configured; in that case, you use the login password (set by the passwd command).
If a aaa authentication http console command statement is not defined, you can gain access to the security appliance using ASDM with no username and the security appliance enable password (set with the enable password command). If the aaa commands are defined, but the HTTP authentication requests a time out, which implies the AAA servers might be down or not available, you can gain access to the security appliance using the default administrator username and the enable password. By default, the enable password is not set.
Examples
The following example shows use of the aaa authentication console command for a Telnet connection to a RADIUS server with the server tag "radius":
hostname(config)# aaa authentication telnet console radiusThe following example identifies the server group "AuthIn" for administrative authentication.
hostname(config)# aaa authentication enable console AuthInThe following example shows use of the aaa authentication console command with fallback to the LOCAL user database if all the servers in the group "srvgrp1" fail:
hostname(config)# aaa-server svrgrp1 protocol tacacs+hostname(config)# aaa authentication serial console srvgrp1 LOCALRelated Commands
aaa authentication listener
To enable HTTP(S) listening ports to authenticate network users, use the aaa authentication listener command in global configuration mode. When you enable a listening port, the security appliance serves an authentication page for direct connections and/or for through traffic. To disable the listeners, use the no form of this command.
aaa authentication listener http[s] interface_name [port portnum] [redirect]
no aaa authentication listener http[s] interface_name [port portnum] [redirect]
Syntax Description
Defaults
By default, no listener services are enabled, and HTTP connections use basic HTTP authentication. If you enable the listeners, the default ports are 80 (HTTP) and 443 (HTTPS).
If you are upgrading from 7.2(1), then the listeners are enabled on ports 1080 (HTTP) and 1443 (HTTPS). The redirect option is also enabled.
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Command History
Usage Guidelines
Without the aaa authentication listener command, when HTTP(S) users need to authenticate with the security appliance after you configure the aaa authentication match or aaa authentication include command, the security appliance uses basic HTTP authentication. For HTTPS, the security appliance generates a custom login screen.
If you configure the aaa authentication listener command with the redirect keyword, the security appliance redirects all HTTP(S) authentication requests to web pages served by the security appliance.
Redirection is an improvement over the basic method because it provides an improved user experience when authenticating, and an identical user experience for HTTP and HTTPS in both Easy VPN and firewall modes. It also supports authenticating directly with the security appliance.
You might want to continue to use basic HTTP authentication if: you do not want the security appliance to open listening ports; if you use NAT on a router and you do not want to create a translation rule for the web page served by the security appliance; basic HTTP authentication might work better with your network. For example non-browser applications, like when a URL is embedded in email, might be more compatible with basic authentication.
If you enter the aaa authentication listener command without the redirect option, then you only enable direct authentication with the security appliance, while letting through traffic use basic HTTP authentication. The redirect option enables both direct and through-traffic authentication. Direct authentication is useful when you want to authenticate traffic types that do not support authentication challenges; you can have each user authenticate directly with the security appliance before using any other services.
Examples
The following example configures the security appliance to redirect HTTP and HTTPS connections to the default ports:
hostname(config)# aaa authentication http redirecthostname(config)# aaa authentication https redirectThe following example allows authentication requests directly to the security appliance; through traffic uses basic HTTP authentication:
hostname(config)# aaa authentication httphostname(config)# aaa authentication httpsThe following example configures the security appliance to redirect HTTP and HTTPS connections to non-default ports:
hostname(config)# aaa authentication http port 1100 redirecthostname(config)# aaa authentication https port 1400 redirectRelated Commands
aaa authentication match
To enable authentication for connections through the security appliance, use the aaa authentication match command in global configuration mode. To disable authentication, use the no form of this command.
aaa authentication match acl_name interface_name {server_tag | LOCAL}
no aaa authentication match acl_name interface_name {server_tag | LOCAL}
Syntax Description
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Command History
Usage Guidelines
You cannot use the aaa authentication match command in the same configuration as the include and exclude commands. We suggest that you use the match command instead of the include and exclude commands; the include and exclude commands are not supported by ASDM.
TCP sessions might have their sequence numbers randomized even if you disable sequence randomization. This occurs when a AAA server proxies the TCP session to authenticate the user before permitting access.
One-Time Authentication
A user at a given IP address only needs to authenticate one time for all rules and types, until the authentication session expires. (See the timeout uauth command for timeout values.) For example, if you configure the security appliance to authenticate Telnet and FTP, and a user first successfully authenticates for Telnet, then as long as the authentication session exists, the user does not also have to authenticate for FTP.
For HTTP or HTTPS authentication, once authenticated, a user never has to reauthenticate, no matter how low the timeout uauth command is set, because the browser caches the string "Basic=Uuhjksdkfhk==" in every subsequent connection to that particular site. This can be cleared only when the user exits all instances of the web browser and restarts. Flushing the cache is of no use.
Applications Required to Receive an Authentication Challenge
Although you can configure the security appliance to require authentication for network access to any protocol or service, users can authenticate directly with HTTP, HTTPS, Telnet, or FTP only. A user must first authenticate with one of these services before the security appliance allows other traffic requiring authentication.
The authentication ports that the security appliance supports for AAA are fixed:
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Security Appliance Authentication Prompts
For Telnet and FTP, the security appliance generates an authentication prompt.
For HTTP, the security appliance uses basic HTTP authentication by default, and provides an authentication prompt. You can optionally configure the security appliance to redirect users to an internal web page where they can enter their username and password (configured with the aaa authentication listener command).
For HTTPS, the security appliance generates a custom login screen. You can optionally configure the security appliance to redirect users to an internal web page where they can enter their username and password (configured with the aaa authentication listener command).
Redirection is an improvement over the basic method because it provides an improved user experience when authenticating, and an identical user experience for HTTP and HTTPS in both Easy VPN and firewall modes. It also supports authenticating directly with the security appliance.
You might want to continue to use basic HTTP authentication if: you do not want the security appliance to open listening ports; if you use NAT on a router and you do not want to create a translation rule for the web page served by the security appliance; basic HTTP authentication might work better with your network. For example non-browser applications, like when a URL is embedded in email, might be more compatible with basic authentication.
After you authenticate correctly, the security appliance redirects you to your original destination. If the destination server also has its own authentication, the user enters another username and password. If you use basic HTTP authentication and need to enter another username and password for the destination server, then you need to configure the virtual http command.
Note
For FTP, a user has the option of entering the security appliance username followed by an at sign (@) and then the FTP username (name1@name2). For the password, the user enters the security appliance password followed by an at sign (@) and then the FTP password (password1@password2). For example, enter the following text.
name> jamiec@jchrichtonpassword> letmein@he110This feature is useful when you have cascaded firewalls that require multiple logins. You can separate several names and passwords by multiple at signs (@).
The number of login attempts allowed differs between the supported protocols:
Static PAT and HTTP
For HTTP authentication, the security appliance checks real ports when static PAT is configured. If it detects traffic destined for real port 80, regardless of the mapped port, the security appliance intercepts the HTTP connection and enforces authentication.
For example, assume that outside TCP port 889 is translated to port 80 (www) and that any relevant access lists permit the traffic:
static (inside,outside) tcp 10.48.66.155 889 192.168.123.10 www netmask 255.255.255.255Then when users try to access 10.48.66.155 on port 889, the security appliance intercepts the traffic and enforces HTTP authentication. Users see the HTTP authentication page in their web browsers before the security appliance allows HTTP connection to complete.
If the local port is different than port 80, as in the following example:
static (inside,outside) tcp 10.48.66.155 889 192.168.123.10 111 netmask 255.255.255.255Then users do not see the authentication page. Instead, the security appliance sends to the web browser an error message indicating that the user must be authenticated prior using the requested service.
Authenticating Directly with the Security Appliance
If you do not want to allow HTTP, HTTPS, Telnet, or FTP through the security appliance but want to authenticate other types of traffic, you can authenticate with the security appliance directly using HTTP or HTTPS by configuring the aaa authentication listener command.
You can authenticate directly with the security appliance at the following URLs when you enable AAA for the interface:
http://interface_ip[:port]/netaccess/connstatus.htmlhttps://interface_ip[:port]/netaccess/connstatus.htmlAlternatively, you can configure virtual Telnet (using the virtual telnet command). With virtual Telnet, the user Telnets to a given IP address configured on the security appliance, and the security appliance provides a Telnet prompt.
Examples
The following set of examples illustrates how to use the aaa authentication match command:
hostname(config)# show access-listaccess-list mylist permit tcp 10.0.0.0 255.255.255.0 192.168.2.0 255.255.255.0 (hitcnt=0) access-list yourlist permit tcp any any (hitcnt=0)hostname(config)# show running-config aaaaaa authentication match mylist outbound TACACS+In this context, the following command:
hostname(config)# aaa authentication match yourlist outbound tacacsis equivalent to this command:
hostname(config)# aaa authentication include TCP/0 outbound 0.0.0.0 0.0.0.0 0.0.0.0 0.0.0.0 tacacsThe aaa command statement list is order-dependent between access-list command statements. If you enter the following command:
hostname(config)# aaa authentication match mylist outbound TACACS+before this command:
hostname(config)# aaa authentication match yourlist outbound tacacsthe security appliance tries to find a match in the mylist access-list command statement group before it tries to find a match in the yourlist access-list command statement group.
Related Commands
aaa authentication secure-http-client
To enable SSL and secure username and password exchange between HTTP clients and the security appliance, use the aaa authentication secure-http-client command in global configuration mode. To disable this function, use the no form of this command. The aaa authentication secure-http-client command offers a secure method for user authentication to the security appliance prior to allowing user HTTP-based web requests to traverse the security appliance.
aaa authentication secure-http-client
no aaa authentication secure-http-client
Syntax Description
This command has no arguments or keywords.
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Usage Guidelines
The aaa authentication secure-http-client command secures HTTP client authentication (through SSL). This command is used for HTTP cut-through proxy authentication.
The aaa authentication secure-http-client command has the following limitations:
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static (inside,outside) tcp 10.132.16.200 www 10.130.16.10 wwwstatic (inside,outside) tcp 10.132.16.200 443 10.130.16.10 443Examples
The following example configures HTTP traffic to be securely authenticated:
hostname(config)# aaa authentication secure-http-clienthostname(config)# aaa authentication include http...where "..." represents your values for authen_service if_name local_ip local_mask [foreign_ip foreign_mask] server_tag.
The following command configures HTTPS traffic to be securely authenticated:
hostname (config)# aaa authentication include https...where "..." represents your values for authentication -service interface-name local-ip local-mask [foreign-ip foreign-mask] server-tag.
Note
Related Commands
aaa authorization
To include or exclude user authorization for traffic through the security appliance using a TACACS+ server, use the aaa authorization command with the include or exclude keywords in global configuration mode. To disable user authorization, use the no form of this command.
aaa authorization {include | exclude} authorization-service interface-name inside-ip inside-mask [outside-ip outside-mask] tacacs+-server-tag
no aaa authorization {include | exclude} authorization-service interface-name inside-ip inside-mask [outside-ip outside-mask] tacacs+-server-tag
Syntax Description
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Command History
7.0(1)
The exclude parameter now allows the user to specify a port to exclude to a specific host or hosts.
Usage Guidelines
You can configure the security appliance to perform network access authorization with TACACS+.
We recommend using the aaa authorization match command instead of the aaa authorization include or exclude command. You cannot use the aaa authorization include or exclude command and the aaa authorization match command in the same configuration. The aaa authorization match command uses an access list to match traffic, and is a more robust command for this feature.
You cannot use the aaa authorization command between same-security interfaces. For that scenario, you must use the aaa authorization match command.
Authentication and authorization statements are independent; however, any unauthenticated traffic matched by an authorization statement will be denied. For authorization to succeed, a user must first authenticate with the security appliance. A specific authorization rule does not require the equivalent authentication. Authentication is required only with FTP, HTTP, or Telnet to provide an interactive way for the user to enter the authorization credentials. Because a user at a given IP address only needs to authenticate one time for all rules and types, if the authentication session has not expired, authorization can occur even if the traffic is matched by an authentication statement.
After a user authenticates, the security appliance checks the authorization rules for matching traffic. If the traffic matches the authorization statement, the security appliance sends the username to the TACACS+ server. The TACACS+ server responds to the security appliance with a permit or a deny for that traffic, based on the user profile. The security appliance enforces the authorization rule in the response.
See the documentation for your TACACS+ server for information about configuring network access authorizations for a user.
If the first attempt at authorization fails and a second attempt causes a timeout, use the service resetinbound command to reset the client that failed the authorization so that it will not retransmit any connections. An example authorization timeout message in Telnet follows.
Unable to connect to remote host: Connection timed outExamples
The following example uses the TACACS+ protocol:
hostname(config)# aaa-server tplus1 protocol tacacs+hostname(config)# aaa-server tplus1 (inside) host 10.1.1.10 thekey timeout 20hostname(config)# aaa authentication include any inside 0 0 0 0 tplus1hostname(config)# aaa authorization include any inside 0 0 0 0hostname(config)# aaa accounting include any inside 0 0 0 0 tplus1hostname(config)# aaa authentication serial console tplus1In this example, the first command statement creates a server group named tplus1 and specifies the TACACS+ protocol for use with this group. The second command specifies that the authentication server with the IP address 10.1.1.10 resides on the inside interface and is in the tplus1 server group. The next three command statements specify that any users starting connections through the outside interface to any foreign host will be authenticated using the tplus1 server group, that the users who are successfully authenticated are authorized to use any service, and that all outbound connection information will be logged in the accounting database. The last command statement specifies that access to the security appliance serial console requires authentication from the tplus1 server group.
The following example enables authorization for DNS lookups from the outside interface:
hostname(config)# aaa authorization include udp/53 outside 0.0.0.0 0.0.0.0The following example enables authorization of ICMP echo-reply packets arriving at the inside interface from inside hosts:
hostname(config)# aaa authorization include 1/0 inside 0.0.0.0 0.0.0.0This means that users cannot ping external hosts if they have not been authenticated using Telnet, HTTP, or FTP.
The following example enables authorization only for ICMP echoes (pings) that arrive at the inside interface from an inside host:
hostname(config)# aaa authorization include 1/8 inside 0.0.0.0 0.0.0.0Related Commands
aaa authorization command
To configure command authorization for management access, use the aaa authorization command command in global configuration mode. To disable command authorization, use the no form of this command.
aaa authorization command {LOCAL | tacacs+-server-tag [LOCAL]}
no aaa authorization command {LOCAL | tacacs+-server-tag [LOCAL]}
Syntax Description
Defaults
Fallback to the local database for authorization is disabled by default.
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Command History
Usage Guidelines
By default when you log in, you can access user EXEC mode, which offers only minimal commands. When you enter the enable command (or the login command when you use the local database), you can access privileged EXEC mode and advanced commands, including configuration commands. If you want to control the access to commands, the security appliance lets you configure command authorization, where you can determine which commands that are available to a user.
You can use one of two command authorization methods:
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Before you enable TACACS+ command authorization, be sure that you are logged into the security appliance as a user that is defined on the TACACS+ server, and that you have the necessary command authorization to continue configuring the security appliance. For example, you should log in as an admin user with all commands authorized. Otherwise, you could become unintentionally locked out.
When configuring command authorization with a TACACS+ server, do not save your configuration until you are sure it works the way you want. If you get locked out because of a mistake, you can usually recover access by restarting the security appliance.
Be sure that your TACACS+ system is completely stable and reliable. The necessary level of reliability typically requires that you have a fully redundant TACACS+ server system and fully redundant connectivity to the security appliance. For example, in your TACACS+ server pool, include one server connected to interface 1, and another to interface 2. You can also configure local command authorization as a fallback method if the TACACS+ server is unavailable.
Examples
The following example shows how to enable command authorization using a TACACS+ server group named tplus1:
hostname(config)#aaa authorization command tplus1The following example shows how to configure administrative authorization to support fallback to the local user database if all servers in the tplus1 server group are unavailable.
hostname(config)#aaa authorization command tplus1 LOCALRelated Commands
aaa authorization match
To enable user authorization for traffic through the security appliance using a TACACS+ server, use the aaa authorization match command in global configuration mode. To disableauthorization, use the no form of this command.
aaa authorization match acl-name interface-name server-tag
no aaa authorization match acl-name interface-name server-tag
Syntax Description
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Command History
Usage Guidelines
You can configure the security appliance to perform network access authorization with TACACS+.
We recommend using the aaa authorization match command instead of the aaa authorization include or exclude command. You cannot use the aaa authorization include or exclude command and the aaa authorization match command in the same configuration. The aaa authorization match command uses an access list to match traffic, and is a more robust command for this feature.
Authentication and authorization statements are independent; however, any unauthenticated traffic matched by an authorization statement will be denied. For authorization to succeed, a user must first authenticate with the security appliance. A specific authorization rule does not require the equivalent authentication. Authentication is required only with FTP, HTTP, or Telnet to provide an interactive way for the user to enter the authorization credentials. Because a user at a given IP address only needs to authenticate one time for all rules and types, if the authentication session has not expired, authorization can occur even if the traffic is matched by an authentication statement.
After a user authenticates, the security appliance checks the authorization rules for matching traffic. If the traffic matches the authorization statement, the security appliance sends the username to the TACACS+ server. The TACACS+ server responds to the security appliance with a permit or a deny for that traffic, based on the user profile. The security appliance enforces the authorization rule in the response.
See the documentation for your TACACS+ server for information about configuring network access authorizations for a user.
If the first attempt at authorization fails and a second attempt causes a timeout, use the service resetinbound command to reset the client that failed the authorization so that it will not retransmit any connections. An example authorization timeout message in Telnet follows.
Unable to connect to remote host: Connection timed outExamples
The following example uses the tplus1 server group with the aaa commands:
hostname(config)#aaa-server tplus1 protocol tacacs+hostname(config)#aaa-server tplus1 (inside) host 10.1.1.10 thekey timeout 20hostname(config)#aaa authentication match authen1 inside tplus1hostname(config)#aaa accounting match acct1 inside tplus1hostname(config)#aaa authorization match myacl inside tplus1In this example, the first command statement defines the tplus1 server group as a TACACS+ group. The second command specifies that the authentication server with the IP address 10.1.1.10 resides on the inside interface and is in the tplus1 server group. The next two command statements specify that any connections traversing the inside interface to any foreign host are authenticated using the tplus1 server group, and that all these connections are logged in the accounting database. The last command statement specifies that any connections that match the ACEs in myacl are authorized by the AAA servers in the tplus1 server group.
Related Commands
aaa local authentication attempts max-fail
To limit the number of consecutive failed local login attempts that the security appliance allows any given user account, use the aaa local authentication attempts max-fail command in global configuration mode. This command only affects authentication with the local user database. To disable this feature and allow an unlimited number of consecutive failed local login attempts, use the no form of this command.
aaa local authentication attempts max-fail number
Syntax Description
number
The maximum number of times a user can enter a wrong password before being locked out. This number can be in the range 1-16.
Defaults
No default behavior or values..
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Usage Guidelines
If you omit this command, there is no limit on the number of times a user can enter an incorrect password.
After a user makes the configured number of attempts with the wrong password, the user is locked out and cannot log in successfully until the administrator unlocks the username. Locking or unlocking a username results in a syslog message.
The administrator cannot be locked out of the device.
The number of failed attempts resets to zero and the lockout status resets to No when the user successfully authenticates or when the security appliance reboots.
Examples
The following example shows use of the aaa local authentication attempts max-limits command to set the maximum number of failed attempts allowed to 2:
hostname(config)# aaa local authentication attempts max-limits 2hostname(config)#Related Commands
aaa mac-exempt
To specify the use of a predefined list of MAC addresses to exempt from authentication and authorization, use the aaa mac-exempt command in global configuration mode. You can only add one aaa mac-exempt command. To disable the use of a list of MAC addresses, use the no form of this command.
aaa mac-exempt match id
no aaa mac-exempt match id
Syntax Description
Defaults
No default behaviors or values.
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Usage Guidelines
Configure the MAC list number using the mac-list command before using the aaa mac-exempt command. Permit entries in the MAC list exempt the MAC addresses from authentication and authorization, while deny entries require authentication and authorization for the MAC address, if enabled. Because you can only add one instance of the aaa mac-exempt command, be sure that your MAC list includes all the MAC addresses you want to exempt.
Examples
The following example bypasses authentication for a single MAC address:
hostname(config)# mac-list abc permit 00a0.c95d.0282 ffff.ffff.ffffhostname(config)# aaa mac-exempt match abcThe following entry bypasses authentication for all Cisco IP Phones, which have the hardware ID 0003.E3:
hostname(config)# mac-list acd permit 0003.E300.0000 FFFF.FF00.0000hostname(config)# aaa mac-exempt match acdThe following example bypasses authentication for a a group of MAC addresses except for 00a0.c95d.02b2:
hostname(config)# mac-list 1 deny 00a0.c95d.0282 ffff.ffff.ffffhostname(config)# mac-list 1 permit 00a0.c95d.0000 ffff.ffff.0000hostname(config)# aaa mac-exempt match 1Related Commands
aaa proxy-limit
To manually configure the uauth session limit by setting the maximum number of concurrent proxy connections allowed per user, use the aaa proxy-limit command in global configuration mode. To disable proxies, use the disable parameter. To return to the default proxy-limit value (16), use the no form of this command.
aaa proxy-limit proxy_limit
aaa proxy-limit disable
no aaa proxy-limit
Syntax Description
disable
No proxies allowed.
proxy_limit
Specify the number of concurrent proxy connections allowed per user, from 1 to 128.
Defaults
The default proxy-limit value is 16.
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Command History
Usage Guidelines
If a source address is a proxy server, consider excluding this IP address from authentication or increasing the number of allowable outstanding AAA requests.
Examples
The following example shows how to set the maximum number of outstanding authentication requests allowed per user:
hostname(config)# aaa proxy-limit 6Related Commands
aaa-server host
To configure a AAA server as part of a AAA server group and to configure AAA server parameters that are host-specific, use the aaa-server host command in global configuration mode. When you use the aaa-server host command, you enter the aaa-server host configuration mode, from which you can specify and manage host-specific AAA server connection data. To remove a host configuration, use the no form of this command:
aaa-server server-tag [(interface-name)] host {server-ip | name} [key] [timeout seconds]
no aaa-server server-tag [(interface-name)] host {server-ip | name} [key] [timeout seconds]
Syntax Description
Defaults
The default timeout value is 10 seconds.
The default interface is inside.
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Usage Guidelines
You control AAA server configuration by defining a AAA server group protocol with the aaa-server protocol command, and then you add servers to the group using the aaa-server host command.
You can have up to 15 server groups in single mode or 4 server groups per context in multiple mode. Each group can have up to 16 servers in single mode or 4 servers in multiple mode. When a user logs in, the servers are accessed one at a time starting with the first server you specify in the configuration, until a server responds.
After you enter the aaa-server host command, you can configure host-specific parameters.
Examples
The following example configures a Kerberos AAA server group named "watchdogs", adds a AAA server to the group, and defines the Kerberos realm for the server.
Note
hostname(config)# aaa-server watchdogs protocol kerberoshostname(config-aaa-server-group)# exithostname(config)# aaa-server watchdogs host 192.168.3.4hostname(config-aaa-server-host)# kerberos-realm EXAMPLE.COMThe following example configures an SDI AAA server group named "svrgrp1", and then adds a AAA server to the group, sets the timeout interval to 6 seconds, sets the retry interval to 7 seconds, and configures the SDI version to version 5.
hostname(config)# aaa-server svrgrp1 protocol sdihostname(config-aaa-server-group)# exithostname(config)# aaa-server svrgrp1 host 192.168.3.4hostname(config-aaa-server-host)# timeout 6hostname(config-aaa-server-host)# retry-interval 7hostname(config-aaa-server-host)# sdi-version sdi-5Related Commands
aaa-server protocol
To create a AAA server group and configure AAA server parameters that are group-specific and common to all group hosts, use the aaa-server protocol command in global configuration mode to enter the AAA-server group mode, from which you can configure these group parameters. To remove the designated group, use the no form of this command.
aaa-server server-tag protocol server-protocol
no aaa-server server-tag protocol server-protocol
Syntax Description
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Command History
Usage Guidelines
You control AAA server configuration by defining a AAA server group protocol with the aaa-server protocol command, and then you add servers to the group using the aaa-server host command.
You can have up to 15 server groups in single mode or 4 server groups per context in multiple mode. Each group can have up to 16 servers in single mode or 4 servers in multiple mode. When a user logs in, the servers are accessed one at a time starting with the first server you specify in the configuration, until a server responds.
After you enter the aaa-server protocol command, you can configure host-specific parameters. For example, if AAA accounting is in effect, the accounting information goes only to the active server unless you have configured simultaneous accounting using the accounting-mode command.
Examples
The following example shows the use of the aaa-server protocol command to modify details of a TACACS+ server group configuration:
hostname(config)# aaa-server svrgrp1 protocol tacacs+hostname(config-aaa-server-group)# accounting-mode simultaneoushostname(config-aaa-server-group)# reactivation mode timedhostname(config-aaa-server-group)# max-failed attempts 2Related Commands
absolute
To define an absolute time when a time range is in effect, use the absolute command in time-range configuration mode. To disable, use the no form of this command.
absolute [end time date] [start time date]
no absolute
Syntax Description
Defaults
If no start time and date are specified, the permit or deny statement is in effect immediately and always on. Similarly, the maximum end time is 23:59 31 December 2035. If no end time and date are specified, the associated permit or deny statement is in effect indefinitely.
Command Modes
The following table shows the modes in which you can enter the command:
Time-range configuration
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Usage Guidelines
To implement a time-based ACL, use the time-range command to define specific times of the day and week. Then use the with the access-list extended time-range command to bind the time range to an ACL.
Examples
The following example activates an ACL at 8:00 a.m. on 1 January 2006:
hostname(config-time-range)# absolute start 8:00 1 January 2006Because no end time and date are specified, the associated ACL is in effect indefinitely.Related Commands
accept-subordinates
To configure the security appliance to accept subordinate CA certificates if delivered during phase one IKE exchange when not previously installed on the device, use the accept-subordinates command in crypto ca trustpoint configuration mode. To restore the default setting, use the no form of the command.
accept-subordinates
no accept-subordinates
Syntax Description
Defaults
The default setting is on (subordinate certificates are accepted).
Command Modes
The following table shows the modes in which you can enter the
Crypto ca trustpoint configuration
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command:
Command History
Usage Guidelines
During phase 1 processing, an IKE peer might pass both a subordinate certificate and an identity certificate. The subordinate certificate might not be installed on the security appliance. This command lets an administrator support subordinate CA certificates that are not configured as trustpoints on the device without requiring that all subordinate CA certificates of all established trustpoints be acceptable; in other words, this command lets the device authenticate a certificate chain without installing the entire chain locally.
Examples
The following example enters crypto ca trustpoint configuration mode for trustpoint central, and allows the security appliance to accept subordinate certificates for trustpoint central:
hostname(config)# crypto ca trustpoint centralhostname(ca-trustpoint)# accept-subordinateshostname(ca-trustpoint)#Related Commands
crypto ca trustpoint
Enters trustpoint configuration mode.
default enrollment
Returns enrollment parameters to their defaults.
access-group
To bind an access list to an interface, use the access-group command in global configuration mode. To unbind an access list from the interface, use the no form of this command.
access-group access-list {in | out} interface interface_name [per-user-override]
no access-group access-list {in | out} interface interface_name
Syntax Description
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Usage Guidelines
The access-group command binds an access list to an interface. The access list is applied to traffic inbound to an interface. If you enter the permit option in an access-list command statement, the security appliance continues to process the packet. If you enter the deny option in an access-list command statement, the security appliance discards the packet and generates the following syslog message.
The per-user-override option allows downloaded access lists to override the access list applied to the interface. If the per-user-override optional argument is not present, the security appliance preserves the existing filtering behavior. When per-user-override is present, the security appliance allows the permit or deny status from the per-user access-list (if one is downloaded) associated to a user to override the permit or deny status from the access-group command associated access list. Additionally, the following rules are observed:
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Always use the access-list command with the access-group command.
The access-group command binds an access list to an interface. The in keyword applies the access list to the traffic on the specified interface. The out keyword applies the access list to the outbound traffic.
Note
The no access-group command unbinds the access list from the interface interface_name.
The show running config access-group command displays the current access list bound to the interfaces.
The clear configure access-group command removes all the access lists from the interfaces.
Examples
The following example shows how to use the access-group command:
hostname(config)# static (inside,outside) 209.165.201.3 10.1.1.3hostname(config)# access-list acl_out permit tcp any host 209.165.201.3 eq 80hostname(config)# access-group acl_out in interface outsideThe static command provides a global address of 209.165.201.3 for the web server at 10.1.1.3. The access-list command lets any host access the global address using port 80. The access-group command specifies that the access-list command applies to traffic entering the outside interface.
Related Commands
access-list alert-interval
To specify the time interval between deny flow maximum messages, use the access-list alert-interval command in global configuration mode. To return to the default settings, use the no form of this command.
access-list alert-interval secs
no access-list alert-interval
Syntax Description
secs
Time interval between deny flow maximum message generation; valid values are from 1 to 3600 seconds.
Defaults
The default is 300 seconds.
Command Modes
The following table shows the modes in which you can enter the command:
Global Configuration
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Usage Guidelines
The access-list alert-interval command sets the time interval for generating the syslog message 106101. The syslog message 106101 alerts you that the security appliance has reached a deny flow maximum. When the deny flow maximum is reached, another 106101 message is generated if at least secs seconds have occurred since the last 106101 message.
See the access-list deny-flow-max command for information about the deny flow maximum message generation.
Examples
The following example shows how to specify the time interval between deny flow maximum messages:
hostname(config)# access-list alert-interval 30Related Commands
access-list deny-flow-max
To specify the maximum number of concurrent deny flows that can be created, use the access-list deny-flow-max command in global configuration mode. To return to the default settings, use the no form of this command.
access-list deny-flow-max
no access-list deny-flow-max
Syntax Description
This command has no arguments or keywords.
Defaults
The default is 4096.
Command Modes
The following table shows the modes in which you can enter the command:
Global Configuration
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Usage Guidelines
Syslog message 106101 is generated when the security appliance has reached the maximum number, n, of ACL deny flows.
Examples
The following example shows how to specify the maximum number of concurrent deny flows that can be created:
hostname(config)# access-list deny-flow-max 256Related Commands
access-list ethertype
To configure an access list that controls traffic based on its EtherType, use the access-list ethertype command in global configuration mode. To remove the access list, use the no form of this command.
access-list id ethertype {deny | permit} {ipx | bpdu | mpls-unicast | mpls-multicast | any | hex_number}
no access-list id ethertype {deny | permit} {ipx | bpdu | mpls-unicast | mpls-multicast | any | hex_number}
Syntax Description
Defaults
The defaults are as follows:
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When the log optional keyword is specified, the default level for syslog message 106100 is 6 (informational).
Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Usage Guidelines
The security appliance can control any EtherType identified by a 16-bit hexadecimal number. EtherType ACLs support Ethernet V2 frames. 802.3-formatted frames are not handled by the ACL because they use a length field as oppsed to a type field. Bridge protocol data units, which are handled by the ACL, are the only exception; they are SNAP-encapsulated, and the security appliance is designed to specifically handle BPDUs.
Because EtherTypes are connectionless, you need to apply the ACL to both interfaces if you want traffic to pass in both directions.
If you allow MPLS, ensure that LDP and TDP TCP connections are established through the security appliance by configuring both MPLS routers connected to the security appliance to use the IP address on the security appliance interface as the router-id for LDP or TDP sessions. (LDP and TDP allow MPLS routers to negotiate the labels (addresses) used to forward packets.)
You can apply only one ACL of each type (extended and EtherType) to each direction of an interface. You can also apply the same ACLs on multiple interfaces.
Note
Examples
The following example shows how to add an EtherType access list:
hostname(config)# access-list ETHER ethertype permit ipxhostname(config)# access-list ETHER ethertype permit bpduhostname(config)# access-list ETHER ethertype permit mpls-unicasthostname(config)# access-group ETHER in interface insideRelated Commands
access-list extended
To add an Access Control Entry, use the access-list extended command in global configuration mode. An access list is made up of one or more ACEs with the same access list ID. Access lists are used to control network access or to specify traffic for many feature to act upon. To remove the ACE, use the no form of this command. To remove the entire access list, use the clear configure access-list command.
access-list id [line line-number] [extended] {deny | permit}
{protocol | object-group protocol_obj_grp_id}
{src_ip mask | interface ifc_name | object-group network_obj_grp_id}
[operator port | object-group service_obj_grp_id]
{dest_ip mask | interface ifc_name | object-group network_obj_grp_id}
[operator port | object-group service_obj_grp_id | object-group icmp_type_obj_grp_id]
[log [[level] [interval secs] | disable | default]]
[inactive | time-range time_range_name]no access-list id [line line-number] [extended] {deny | permit} {tcp | udp}
{src_ip mask | interface ifc_name | object-group network_obj_grp_id}
[operator port] | object-group service_obj_grp_id]
{dest_ip mask | interface ifc_name | object-group network_obj_grp_id}
[operator port | object-group service_obj_grp_id | object-group icmp_type_obj_grp_id]
[log [[level] [interval secs] | disable | default]]
[inactive | time-range time_range_name]Syntax Description
Defaults
The defaults are as follows:
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Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Usage Guidelines
Each ACE that you enter for a given access list name is appended to the end of the access list unless you specify the line number in the ACE.
The order of ACEs is important. When the security appliance decides whether to forward or drop a packet, the security appliance tests the packet against each ACE in the order in which the entries are listed. After a match is found, no more ACEs are checked. For example, if you create an ACE at the beginning of an access list that explicitly permits all traffic, no further statements are ever checked.
Access lists have an implicit deny at the end of the list, so unless you explicitly permit it, traffic cannot pass. For example, if you want to allow all users to access a network through the security appliance except for particular addresses, then you need to deny the particular addresses and then permit all others.
When you use NAT, the IP addresses you specify for an access list depend on the interface to which the access list is attached; you need to use addresses that are valid on the network connected to the interface. This guideline applies for both inbound and outbound access groups: the direction does not determine the address used, only the interface does.
For TCP and UDP connections, you do not need an access list to allow returning traffic, because the FWSM allows all returning traffic for established, bidirectional connections. For connectionless protocols such as ICMP, however, the security appliance establishes unidirectional sessions, so you either need access lists to allow ICMP in both directions (by applying access lists to the source and destination interfaces), or you need to enable the ICMP inspection engine. The ICMP inspection engine treats ICMP sessions as bidirectional connections.
Because ICMP is a connectionless protocol, you either need access lists to allow ICMP in both directions (by applying access lists to the source and destination interfaces), or you need to enable the ICMP inspection engine. The ICMP inspection engine treats ICMP sessions as stateful connections. To control ping, specify echo-reply (0) (security appliance to host) or echo (8) (host to security appliance). See Table 1 for a list of ICMP types.
You can apply only one access list of each type (extended and EtherType) to each direction of an interface. You can apply the same access lists on multiple interfaces. See the access-group command for more information about applying an access list to an interface.
Note
Table 1 lists the possible ICMP types values.
Examples
The following access list allows all hosts (on the interface to which you apply the access list) to go through the security appliance:
hostname(config)# access-list ACL_IN extended permit ip any anyThe following sample access list prevents hosts on 192.168.1.0/24 from accessing the 209.165.201.0/27 network. All other addresses are permitted.
hostname(config)# access-list ACL_IN extended deny tcp 192.168.1.0 255.255.255.0 209.165.201.0 255.255.255.224hostname(config)# access-list ACL_IN extended permit ip any anyIf you want to restrict access to only some hosts, then enter a limited permit ACE. By default, all other traffic is denied unless explicitly permitted.
hostname(config)# access-list ACL_IN extended permit ip 192.168.1.0 255.255.255.0 209.165.201.0 255.255.255.224The following access list restricts all hosts (on the interface to which you apply the access list) from accessing a website at address 209.165.201.29. All other traffic is allowed.
hostname(config)# access-list ACL_IN extended deny tcp any host 209.165.201.29 eq wwwhostname(config)# access-list ACL_IN extended permit ip any anyThe following access list that uses object groups restricts several hosts on the inside network from accessing several web servers. All other traffic is allowed.
hostname(config-network)# access-list ACL_IN extended deny tcp object-group denied object-group web eq wwwhostname(config)# access-list ACL_IN extended permit ip any anyhostname(config)# access-group ACL_IN in interface insideTo temporarily disable an access list that permits traffic from one group of network objects (A) to another group of network objects (B):
hostname(config)# access-list 104 permit ip host object-group A object-group B inactiveTo implement a time-based access list, use the time-range command to define specific times of the day and week. Then use the access-list extended command to bind the time range to an access list. The following example binds an access list named "Sales" to a time range named "New_York_Minute":
hostname(config)# access-list Sales line 1 extended deny tcp host 209.165.200.225 host 209.165.201.1 time-range New_York_Minutehostname(config)#See the time-range command for more information about how to define a time range.
Related Commands
access-list remark
To specify the text of the remark to add before or after an access-list extended command, use the access-list remark command in global configuration mode. To delete the remark, use the no form of this command.
access-list id [line line-num] remark text
no access-list id [line line-num] remark [text]
Syntax Description
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Global Configuration
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Command History
Usage Guidelines
The remark text can be up to 100 characters in length, including spaces and punctuation. The remark text must contain at least 1 non-space character; you cannot enter an empty remark.
You cannot use the access-group command on an ACL that includes a remark only.
Examples
The following example shows how to specify the text of the remark to add before or after an access-list command:
hostname(config)# access-list 77 remark checklistRelated Commands
access-list standard
To add an access list to identify the destination IP addresses of OSPF routes, which can be used in a route map for OSPF redistribution, use the access-list standard command in global configuration mode. To remove the access list, use the no form of this command.
access-list id standard [line line-num] {deny | permit} {any | host ip_address | ip_address subnet_mask}
no access-list id standard [line line-num] {deny | permit} {any | host ip_address | ip_address subnet_mask}
Syntax Description
Defaults
The defaults are as follows:
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Command Modes
The following table shows the modes in which you can enter the command:
Global configuration
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Usage Guidelines
When used with the access-group command, the deny optional keyword does not allow a packet to traverse the security appliance. By default, the security appliance denies all packets on the originating interface unless you specifically permit access.
Use the following guidelines for specifying a source, local, or destination address:
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Examples
The following example shows how to deny IP traffic through the firewall:
hostname(config)# access-list 77 standard denyThe following example shows how to permit IP traffic through the firewall if conditions are matched:
hostname(config)# access-list 77 standard permitThe following example shows how to specify a destination address:
hostname(config)# access-list 77 standard permit host 10.1.10.123Related Commands
access-list webtype
To add an access list to the configuration that supports filtering for WebVPN, use the access-list webtype command in global configuration mode. To remove the access list, use the no form of this command.
access-list id webtype {deny | permit} url [url_string | any] [log [[disable | default] | level] [interval secs] [time_range name]]
no access-list id webtype {deny | permit} url [url_string | any] [log [[disable | default] | level] [interval secs] [time_range name]]
access-list id webtype {deny | permit} tcp [host ip_address | ip_address subnet_mask | any] [oper port [port]] [log [[disable | default] | level] [interval secs] [time_range name]]
no access-list id webtype {deny | permit} tcp [host ip_address | ip_address subnet_mask | any] [oper port [port]] [log [[disable | default] | level] [interval secs] [time_range name]]
Syntax Description
Defaults
The defaults are as follows:
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The following table shows the modes in which you can enter the command:
Global Configuration
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Usage Guidelines
The access-list webtype command is used to configure WebVPN filtering. The url specified may be full or partial (no file specified), may include wildcards for the server, or may specify a port.
Valid protocol identifiers are: http, https, cifs, imap4, pop3, and smtp. The url may also contain the keyword any to refer to any url. An asterisk may be used to refer to a subcomponent of a DNS name.
Examples
The following example shows how to deny access to a specific company url:
hostname(config)# access-list acl_company webtype deny url http://*.company.comThe following example shows how to deny access to a specific file:
hostname(config)# access-list acl_file webtype deny url https://www.company.com/dir/file.htmlThe following example shows how to deny http access to anywhere through port 8080:
hostname(config)# access-list acl_company webtype deny url http://my-server:8080/*Related Commands
accounting-mode
To indicate whether accounting messages are sent to a single server (single mode) or sent to all servers in the group (simultaneous mode), use the accounting-mode command in AAA-server group mode. To remove the accounting mode specification, use the no form of this command:
accounting-mode {simultaneous | single}
Syntax Description
simultaneous
Sends accounting messages to all servers in the group.
single
Sends accounting messages to a single server.
Defaults
The default value is single mode
Command Modes
The following table shows the modes in which you can enter the command:
AAA-server group
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Usage Guidelines
Use the keyword single to send accounting messages to a single server. Use the keyword simultaneous to send accounting messages to all servers in the server group.
This command is meaningful only when the server group is used for accounting (RADIUS or TACACS+).
Examples
The following example shows the use of the accounting-mode command to send accounting messages to all servers in the group:
hostname(config)# aaa-server svrgrp1 protocol tacacs+hostname(config-aaa-server-group)# accounting-mode simultaneoushostname(config-aaa-server-group)# exithostname(config)#Related Commands
accounting-port
To specify the port number used for RADIUS accounting for this host, use the accounting-port command in AAA-server host mode. To remove the authentication port specification, use the no form of this command. This command specifies the destination TCP/UDP port number of the remote RADIUS server hosts to which you want to send accounting records:
accounting-port port
no accounting-port
Syntax Description
Defaults
By default, the device listens for RADIUS on port 1646 for accounting (in compliance with RFC 2058). If the port is not specified, the RADIUS accounting default port number (1646) is used.
Command Modes
The following table shows the modes in which you can enter the command:
AAA-server host
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Usage Guidelines
If your RADIUS accounting server uses a port other than 1646, you must configure the security appliance for the appropriate port prior to starting the RADIUS service with the aaa-server command.
This command is valid only for server groups that are configured for RADIUS.
Examples
The following example configures a RADIUS AAA server named "srvgrp1" on host "1.2.3.4", sets a timeout of 9 seconds, sets a retry-interval of 7 seconds, and configures accounting port 2222.
hostname(config)# aaa-server svrgrp1 protocol radiushostname(config-aaa-server-group)# aaa-server svrgrp1 host 1.2.3.4hostname(config-aaa-server-host)# timeout 9hostname(config-aaa-server-host)# retry-interval 7hostname(config-aaa-server-host)# accountinq-port 2222hostname(config-aaa-server-host)# exithostname(config)#Related Commands
accounting-server-group
To specify the aaa-server group for sending accounting records, use the accounting-server-group command in tunnel-group general-attributes configuration mode. To return this command to the default, use the no form of this command.
accounting-server-group server-group
no accounting-server-group
Syntax Description
Defaults
The default setting for this command is NONE.
Command Modes
The following table shows the modes in which you can enter the command:
Tunnel-group general attributes configuration
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7.0(1)
This command was introduced.
7.1(1)
Moved this command to the tunnel-group general-attributes configuration mode from the webvpn configuration mode.
Usage Guidelines
You can apply this attribute to all tunnel-group types.
Examples
The following example entered in tunnel-group-general attributes configuration mode, configures an accounting server group named "aaa-server123" for an IPSec LAN-to-LAN tunnel group "xyz":
hostname(config)# tunnel-group xyz type IPSec_L2Lhostname(config)# tunnel-group xyz general-attributeshostname(config-tunnel-general)# accounting-server-group aaa-server123hostname(config-tunnel-general)#Related Commands
accounting-server-group (webvpn)
To specify the set of accounting servers to use with WebVPN or e-mail proxy, use the accounting-server-group command. For WebVPN, use this command in webvpn mode. For e-mail proxies (IMAP4S. POP3S, SMTPS), use this command in the applicable e-mail proxy mode. To remove accounting servers from the configuration, use the no form of this command.
The security appliance uses accounting to keep track of the network resources that users access.
accounting-server-group group tag
no accounting-server-group
Syntax Description
group tag
Identifies the previously configured accounting server or group of servers. Use the aaa-server command to configure accounting servers. Maximum length of the group tag is 16 characters.
Defaults
No accounting servers are configured by default.
Command Modes
The following table shows the modes in which you can enter the command:
Webvpn
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Usage Guidelines
In Release 7.1(1), if you enter this command in webvpn configuration mode, it is transformed to the same command in tunnel-group general-attributes mode.
Examples
The following example shows how to configure WebVPN services to use the set of accounting servers named WEBVPNACCT:
hostname(config)# webvpnhostname(config-webvpn)# accounting-server-group WEBVPNACCTThe following example shows how to configure POP3S e-mail proxy to use the set of accounting servers named POP3SSVRS:
hostname(config)# pop3shostname(config-pop3s)# accounting-server-group POP3SSVRSRelated Commands
aaa-server host
Configures authentication, authorization, and accounting servers.
