Core Issue
This problem is caused by a software issue. The logging synchronous command is used to synchronize unsolicited messages and debug output with solicited Cisco IOS Software output.
Resolution
When the syslog logging stops working, disabling the logging synchronous command on the console line may cause logging to resume.
To disable the logging synchronous command, perform these steps:
- To see if the logging synchronous command is enabled on the console line, issue the show run command. Look under the
line con 0, which is toward the end of the show run command output, as shown:Router#show run
!
line con 0
logging synchronous
line aux 0
line vty 0 4
login
!
end
- If the logging synchronous command is enabled and you want to disable it, issue these commands:
Router#config t
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#line con 0
Router(config-line)#no logging synchronous
Router(config-line)#^Z
Router#write mem
If you do not want to disable the logging synchronous command, perform these steps:
- Upgrade the Cisco IOS Software version.
- To see if the Cisco IOS Software running on the router is affected by Cisco bug ID CSCdu60369, refer to the Bug Toolkit.
- If it is affected, upgrade to a version of Cisco IOS Software in which the bug is resolved.
- If it is not affected, search for other bugs involving syslog logging issues.
When Problem Occurs
After software configuration change
