Cool Linux Tips & Tricks

Linux is an amazing OS because you can do a lot inside it. Here is a bunch of Tips & Tricks I have found.

Find the current time in the timezone you want:

$ TZ='America/Los_Angeles' date
Tue Dec 11 04:07:18 PST 2018

$ TZ='Europe/London' date
Tue Dec 11 12:08:49 GMT 2018

Note: All available timezones can be found at /usr/share/zoneinfo. I recommend to view it using timedatectl list-timezones command.

$ timedatectl list-timezones | grep Europe

Generate random password string using date and md5sum or sha256sum

$ date | sha256sum | base64 | head -c 8 ; echo
Y2RhODhh

$ date | md5sum | base64 | head -c 8 ; echo
YWNjYzU4

Generate pseudo-random string using OpenSSL

$ openssl rand -hex 8

d0388693bd744e0e

$ openssl rand -base64 32 | head -c 12 ; echo

uvics5KjODkt

Generate random password string using gpg utility

$ gpg --gen-random --armor 1 12

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How to replace Supermicro IPMI SSL and TLS Certificate

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