Linux and Windows server administrators commonly need to view and monitor application, system and security logs. Of course, most of these logs in Windows servers are viewed in the aptly named Event Viewer, while most logs in Linux are just lines appended to simple ASCII text files by the syslogd service.
One thing I find very helpful is the ability to monitor Linux syslog messages from my Windows desktop in real-time. To accomplish this, I usually set up an old PC, or preferably use a dual-monitor configuration on my primary PC, so that I have plenty of screen space, then I use Putty to establish several ssh sessions (although telnet will also work) in different windows. Then I arrange the windows in some location where they're unlikely to be covered up by some other application.
Next, I run the "tail" command on several of the event logs. For example, if you want to monitor the "messages" log, you would type the command "tail –f /var/log/messages" into one of the windows. This will cause the contents of the file to be displayed on the screen, much as if you'd typed "cat /var/log/messages", except you don't get your prompt back. When the command reaches the end of file, it just sits there and waits. As soon as syslog puts another event in the file, it is immediately displayed in your window.
So browse through /var/log and decide which logs you want to monitor, then create one ssh session for each and run the "tail" command once in each window.
If you work with a team of administrators all in the same room, consider dedicating an old PC to this task and swapping your monitor for a projector.
Thomas Alexander Lancaster IV is a consultant and author with over ten years experience in the networking industry, focused on Internet infrastructure.
This was first published in October 2003