Cisco IOS Cookbook, 2nd Edition

Using a Remote Log Server

Problem

You want to send log messages to a remote syslog server.

Solution

Use the following command to send router log messages to a remote syslog server:

Router#configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#logging 172.25.1.1
Router(config)#end 
Router#

Although configuring the router with a static IP address like this is the preferred method of configuring a syslog server, you can also specify a hostname to be resolved:

Router#configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#ip host nms.oreilly.com 172.25.1.1
Router(config)#logging nms.oreilly.com
Router(config)#end 
Router#

With this configuration, the router will attempt to resolve the server name that is provided. If the router cannot resolve the server name via DNS or static host lookup, then the entry will fail. For more information about DNS and static host names, please see Chapter 2.

Beginning with IOS Version 12.2(15)T, logging host replaced the logging command; however, both methods are still supported:

Router2#configure terminal 
Enter configuration commands, one per line.  End with CNTL/Z.
Router2(config)#logging host 172.25.1.1
Router2(config)#end
Router2#

Discussion

Forwarding log messages to a remote syslog server has several advantages over just retaining log messages locally on the router. The primary advantage is that messages sent to the server are stored to disk. All other forms of router logging are ...