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Generate a random password

Terminal - Generate a random password
openssl rand -base64 12
2011-07-06 17:48:26
User: Mozai
3
Generate a random password

Another password maker, for human-unfriendly passwords. '-base64' output will make sure it it can be typed on a keyboard, though the output string length will always be a multiple of 4.

Alternatives

There is 1 alternative - vote for the best!

Terminal - Alternatives
strings /dev/urandom | grep -o '[[:alnum:]]' | head -n 30 | tr -d '\n'; echo
2009-02-16 00:39:28
User: jbcurtis
Functions: grep head strings tr
45

Find random strings within /dev/urandom. Using grep filter to just Alphanumeric characters, and then print the first 30 and remove all the line feeds.

gpg --gen-random --armor 1 30
2011-07-20 15:32:49
User: atoponce
Functions: gpg
10

According to the gpg(1) manual:

--gen-random 0|1|2 count

Emit count random bytes of the given quality level 0, 1 or 2. If count is not given or zero, an endless sequence of random bytes will be emitted. If used with --armor the output will be base64 encoded. PLEASE, don't use this command unless you know what you are doing; it may remove precious entropy from the system!

If your entropy pool is critical for various operations on your system, then using this command is not recommended to generate a secure password. With that said, regenerating entropy is as simple as:

du -s /

This is a quick way to generate a strong, base64 encoded, secure password of arbitrary length, using your entropy pool (example above shows a 30-character long password).

cat /dev/urandom | tr -dc A-Za-z0-9 | head -c 32
pwgen 30 1
2011-07-24 19:43:48
User: sairon
6

The pwgen program generates passwords which are designed to be easily memorized by humans, while being as secure as possible. Human-memorable passwords are never going to be as secure as completely completely random passwords. [from pwgen man page]

tr -cd '[:alnum:]' < /dev/urandom | fold -w30 | head -n1

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