Lesson Contents
Change notification is a nice feature on Cisco IOS devices that lets you keep track of the changes that have been made to your configuration. It can even track the user who made these changes and it can send this information to a syslog server.
This is one of those features that is very useful when something suddenly doesn’t work anymore and everyone tells you that “nobody made any changes”.
Configuration
Let’s look at a Cisco router where we enable this feature:
Router(config)#archive
Router(config-archive)#log config
Router(config-archive-log-cfg)#logging enable
First, you should use the archive
command and then enter the log config
section. Use the logging enable
command, and the router will keep track of the configuration changes. There are a number of other items that are useful to configure, however:
Router(config-archive-log-cfg)#logging size 1000
By default, your router will keep 100 entries in the configuration log but we can increase it to 1000 using the logging size
command. All the changes will be kept locally on your router, but we can send it to the syslog server if we want:
Router(config-archive-log-cfg)#notify syslog
Last but not least, it might be a good idea not to store any passwords in the configuration change logs. You can use the following command to disable this:
Router(config-archive-log-cfg)#hidekeys
Verification
Whenever you make a change to the configuration, you will see the following message on your console:
Router#configure terminal
Router(config)#interface loopback 0
Router(config-if)#
%PARSER-5-CFGLOG_LOGGEDCMD: User:console logged command:interface loopback 0
You can see the change that was made (interface loopback 0) and the user that did this (console). Let’s make some more changes to the configuration of this router:
Router(config-if)#shutdown
Router(config-if)#no shutdown
You will see these changes on the console:
Router#
%PARSER-5-CFGLOG_LOGGEDCMD: User:console logged command:shutdown
%PARSER-5-CFGLOG_LOGGEDCMD: User:console logged command:no shutdown
We can also use some show commands to verify what changes have been made:
Router#show archive log config all
idx sess user@line Logged command
1 1 console@console | logging enable
2 1 console@console | logging size 1000
3 1 console@console | notify syslog
4 1 console@console | hidekeys
5 1 console@console | interface loopback 0
6 1 console@console | shutdown
7 1 console@console | no shutdown
Above, you find all the commands that I typed in the console so far. If you want to re-use some of the commands that you found then there’s a useful command for you to use:
Rene,
How do we send this to the syslog server? I saw a command notify syslog don’t we need an IP address?
Please clarify.
Thanks
Hamood
Hi Hamood,
“notify syslog” will ensure that configuration change will send messages to syslog but you will still need to configure syslog to send messages to an external syslog server. Here’s how it’s done:
https://networklessons.com/network-management/cisco-ios-syslog-messages/
Rene
Hi Rene,
Can you please give me the equivalent of these command for IOS XR?
Hope to hear from you soonest.
Hi Adekunle,
IOS XR has a similar mechanism. You can view the commit list and its changes:
Above you can see two changes have been made through
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