Summary: How to send cisco logging to a linux syslog server.
Date: Around 2017
Refactor: 20 February 2025: Checked links and formatting.
All commands assume you've already logged on to the switch with privilege level 15 access and are already in config mode (conf t).
To make sure the logs are displaying the correct timestamp first configure the date and time correctly.
ntp server 10.10.10.123
clock timezone CET +1
clock summer-time CET recurring 1 Sunday April 2:00 last Sunday October 3:00
switch04#show clock 15:15:53.642 CET Thu Sep 23 2010
Correct!
service timestamp log datetime localtime
no logging console no logging monitor logging syslog.company.local
logging trap 6
Note:
switch04(config)#logging trap ? <0-7> Logging severity level emergencies System is unusable (severity=0) alerts Immediate action needed (severity=1) critical Critical conditions (severity=2) errors Error conditions (severity=3) warnings Warning conditions (severity=4) notifications Normal but significant conditions (severity=5) informational Informational messages (severity=6) debugging Debugging messages (severity=7)
logging facility auth
logging source-interface Vlan1 logging on
switch04#show logging
Syslog logging: enabled (0 messages dropped, 0 messages rate-limited, 0 flushes, 0 overruns)
Console logging: level debugging, 2023 messages logged
Monitor logging: level debugging, 0 messages logged
Buffer logging: level debugging, 2023 messages logged
Exception Logging: size (4096 bytes)
File logging: disabled
Trap logging: level informational, 2043 message lines logged
Logging to 10.10.10.14, 1 message lines logged
Now check the configuration, and only write the configuration to the cisco device if everything is correct. To do so:
write exit
The logging of configuration changes was introduced with IOS version 12.3. Since we're running 12.1 with no option to upgrade to 12.3 no testing there. All possibilities are described here: http://www.cisco.com/en/US/docs/ios/12_3t/12_3t4/feature/guide/gtconlog.html
More logging info: http://www.cisco.com/en/US/docs/ios/netmgmt/command/reference/nm_09.html