Can anyone point out some useful commands I should keep note of for checking a unix server box? Like checking the HD for errors, and basically if there has been any probs etc. TIA

Well there is fsck for hard disks. If anything is wrong it shoud be in logs. Are you suspicious of some hardware failing or what?

root:~# tail -f /var/log/all.log

(of course, it's commented out in the config so change that in syslog.conf) but all.log will show you pretty much everything on the server.

As the previous member said,'fsck' is for checking your HD, but what do you mean if there's any problems, etc? What kind of checking do you need performed? If you need security checking, you can use the chkrootkit software from www.chkrootkit.org. It checks your system for trojans and illegally modified binaries.
If you need any other checks, please specify what needs to be checked. Apart from that, logs are probably a good place to look. Have a good day...

Just as a general newby I wanted to learn a few basics that I should check rather than "I want to check"... e.g. On Windows I run a scan disk once in a while and a defrag, is there a defrag neede on unix? etc. Just learning basically! :)

http://www.devside.net/web/guidance/linux/sysadmin

I'll be putting more on that page, but for now...those are some basics for after login.

> hdparm -Tt /dev/hda

...will perform a basic performance test.

If you use fsck, make sure you umount the drive first unless you don't value your data.