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[adeel.sid]

Hello LINUX Champs!!!!
i recently started to use LINUX.I want to know whether it is possible to do following by LINUX commands:
1. checking for no.of users already using sys thru (ofcourse allowed)
2. checking (as root) who is doing what
3. restricting/watching online user at that instant

I will be glad to know if there is more command related to above.
Kind regards
and
Thanx in adv.

 

[paragkalra]

1. checking for no.of users already using sys thru (ofcourse allowed)

#users

2. checking (as root) who is doing what

https://www.cyberciti.biz/faq/linux-unix-find-out-what-other-users-are-doing/

3. restricting/watching online user at that instant

You will have to configure squid/proxy server.

 

[nidhisahu]

sys admin commands

like "w" give u all login names

try to dowload oreily

Linux admin ebook for all commands