Most of users running VPS / Dedicated servers have some basic Linux knowledge.

We will here write some basic linux commands that can help you.

top - command showing process and Cpu usage
ifconfig - command showing your network setup
apt-get update - update instalable packages
apt-get install *package* -  change  *package* with package name that you wish to install in your server
uptime - server uptime
uname -a   - providing OS and kernel type informations
killall -9 *process_name*   -  *process_name* change it with process name you want to kill,

This is just small part of linux commands, there are lot of them available for your command