SAM (system administration menu), sysadmsh
Why is it not a good idea to always login as root?
Why is it dangerous to turn the power off without shutting down properly?
cope with lost passwords
answer hundreds of questions!
What is your own group, user id? Have a look at the /etc/passwd file and the /etc/group file.
file system versus filesystem
tar -cvf /tmp/bkup11.26.97 /Users/upriss
tar -rvf /dev/rmt/0m /tmp/bkup11.26.97.gz
check the file system integrity
tar one of your directories into a file, gzip it, then gunzip it and extract it (tar -xvf).
Subscribe to the appropriate mailing lists for updates.
Disable all inet services that are not required (especially rlogin, finger, systat). Install safe versions of the services that are required. The files "hosts.allow" and "hosts.deny".
Check the /etc/passwd file from time to time.
Type "last|more". Have a look at the files in /etc/inet, especially /etc/inet/inetd.conf.