Couple of them I remember from my first interview
How to configure ssh password less (ssh keys based ) login
Apache configure SSL certificate
Find out who is eating CPU and memory
Process and command accounting/auditing commands
Iptables to block syn flood attack
I am sure others will post more and good luck with job interview

__________________
Rocky Jr.
You may have my body & soul, but you will never touch my pride!
If you have knowledge, let others light their candles at it.
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