Misc SysAdmin

Miscellaneous

This page contains miscellaneous snippets that I pick up that I haven't been able to group into bigger concepts yet.

• In the sudoers file : #includedir is not a comment. It's a directive that points to supplemental config files. There are several other #include directives. This mimics C syntax.
• fail2ban : a great way to get rid of spammers / brute force attacks. Thanks Yarik!
• HP iLO power button options: https://www.experts-exchange.com/questions/27971206/HP-iLO.html
• git branch != git checkout for creating a new branch using the CLI.
• Fiber (specialized form of thread)
• cat /dev/null > /path/to/log allows you to wipe a log without restarting any associated process / daemon
• ZeroMQ references:
  • http://nichol.as/zeromq-an-introduction
  • http://intothesaltmine.readthedocs.io/en/latest/chapters/command-and-control/zeromq.html
  • https://news.ycombinator.com/item?id=2428004
• gpasswd - it exists ; it is a good way to remove users from groups etc
• modules are often more useful than grains in getting system info in salt / just because a grain doesn't exist, doesn't mean there isn't an easy way to get it that's not cmd.run

Outside Links to be Sorted:

https://teachyourselfcs.com https://www.aosabook.org

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Systems-Administration