Examples
The following is
sample output from the
show
debugging command. In this example, the remote
host is not configured or connected.
Router# show debugging
!
TCP:
TCP Packet debugging is on
TCP ECN debugging is on
!
Router# telnet 10.1.25.234
!
Trying 10.1.25.234 ...
!
00:02:48: 10.1.25.31:11001 <---> 10.1.25.234:23 out ECN-setup SYN
00:02:48: tcp0: O CLOSED 10.1.25.234:11001 10.1.25.31:23 seq 1922220018
OPTS 4 ECE CWR SYN WIN 4128
00:02:50: 10.1.25.31:11001 <---> 10.1.25.234:23 congestion window changes
00:02:50: cwnd from 1460 to 1460, ssthresh from 65535 to 2920
00:02:50: tcp0: R SYNSENT 10.1.25.234:11001 10.1.25.31:23 seq 1922220018
OPTS 4 ECE CWR SYN WIN 4128
00:02:54: 10.1.25.31:11001 <---> 10.1.25.234:23 congestion window changes
00:02:54: cwnd from 1460 to 1460, ssthresh from 2920 to 2920
00:02:54: tcp0: R SYNSENT 10.1.25.234:11001 10.1.25.31:23 seq 1922220018
OPTS 4 ECE CWR SYN WIN 4128
00:03:02: 10.1.25.31:11001 <---> 10.1.25.234:23 congestion window changes
00:03:02: cwnd from 1460 to 1460, ssthresh from 2920 to 2920
00:03:02: tcp0: R SYNSENT 10.1.25.234:11001 10.1.25.31:23 seq 1922220018
OPTS 4 ECE CWR SYN WIN 4128
00:03:18: 10.1.25.31:11001 <---> 10.1.25.234:23 SYN with ECN disabled
00:03:18: 10.1.25.31:11001 <---> 10.1.25.234:23 congestion window changes
00:03:18: cwnd from 1460 to 1460, ssthresh from 2920 to 2920
00:03:18: tcp0: O SYNSENT 10.1.25.234:11001 10.1.25.31:23 seq 1922220018
OPTS 4 SYN WIN 4128
00:03:20: 10.1.25.31:11001 <---> 10.1.25.234:23 congestion window changes
00:03:20: cwnd from 1460 to 1460, ssthresh from 2920 to 2920
00:03:20: tcp0: R SYNSENT 10.1.25.234:11001 10.1.25.31:23 seq 1922220018
OPTS 4 SYN WIN 4128
00:03:24: 10.1.25.31:11001 <---> 10.1.25.234:23 congestion window changes
00:03:24: cwnd from 1460 to 1460, ssthresh from 2920 to 2920
00:03:24: tcp0: R SYNSENT 10.1.25.234:11001 10.1.25.31:23 seq 1922220018
OPTS 4 SYN WIN 4128
00:03:32: 10.1.25.31:11001 <---> 10.1.25.234:23 congestion window changes
00:03:32: cwnd from 1460 to 1460, ssthresh from 2920 to 2920
00:03:32: tcp0: R SYNSENT 10.1.25.234:11001 10.1.25.31:23 seq 1922220018
OPTS 4 SYN WIN 4128
!Connection timed out; remote host not responding
The following is
sample output from the
show
debugging command when user-group debugging is
configured:
Router# show debugging
!
usergroup:
Usergroup Deletions debugging is on
Usergroup Additions debugging is on
Usergroup Database debugging is on
Usergroup API debugging is on
!
The following is
sample output from the
show
debugging command when SNAP debugging is
configured:
Router# show debugging
Persistent variable debugging is currently All
SNAP Server Debugging ON
SNAP Client Debugging ON
Router#
The table below
describes the significant fields in the output.
Table 1 show debugging Field Descriptions
Field
|
Description
|
OPTS 4
|
Bytes of
TCP expressed as a number. In this case, the bytes are 4.
|
ECE
|
Echo
congestion experience.
|
CWR
|
Congestion
window reduced.
|
SYN
|
Synchronize connections--Request to synchronize sequence numbers, used when a
TCP connection is being opened.
|
WIN 4128
|
Advertised window size, in bytes. In this case, the bytes are 4128.
|
cwnd
|
Congestion window (cwnd)--Indicates that the window size has changed.
|
ssthresh
|
Slow-start threshold (ssthresh)--Variable used by TCP to determine whether or
not to use slow-start or congestion avoidance.
|
usergroup
|
Statically defined usergroup to which source IP addresses are associated.
|