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Generate a Random Password

Terminal - Generate a Random Password
dd if=/dev/urandom bs=1 count=32 2>/dev/null | base64 -w 0 | rev | cut -b 2- | rev
2009-02-17 23:36:24
User: TyIzaeL
Functions: cut dd rev
0
Generate a Random Password

I know there are a lot of random password generators out there, but I wanted something that put out something besides hex. Set count equal to the number of bytes you want.

Alternatives

There are 4 alternatives - 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
44

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.

pwgen -Bs 10 1
2009-12-01 14:33:51
14

-B flag = don't include characters that can be confused for other characters (this helps when you give someone their password for the first time so they don't cause a lockout with, for example, denyhosts or fail2ban)

-s flag = make a "secure", or hard-to-crack password

-y flag = include special characters (not used in the example because so many people hate it -- however I recommend it)

"1 10" = output 1 password, make it 10 characters in length

For even more secure passwords please use the -y flag to include special characters like so:

pwgen -Bsy 10 1

output>> }&^Y?.>7Wu

< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c6
2009-02-24 09:43:40
User: Blackbit
Functions: head tr
11

If you want a password length longer than 6, changing the -c6 to read -c8 will give you 8 random characters instead of 6. To end up with a line-feed, use this with echo:

# echo `< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c6`

randpw(){ < /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c${1:-16};echo;}
2009-08-07 07:30:57
User: frozenfire
Functions: head tr
3

Generates password consisting of alphanumeric characters, defaults to 16 characters unless argument given.

dd bs=1 count=32 if=/dev/random 2> /dev/null | md5 | grep -o '\w*'

Know a better way?

If you can do better, submit your command here.

What others think

Genial! :)

Comment by kornykyano 332 weeks and 6 days ago

Won't work on OSX as is - try

dd if=/dev/urandom bs=1 count=32 2>/dev/null |openssl enc -base64|rev|cut -b 2-|rev

for a more universal version

Comment by furicle 332 weeks and 5 days ago

Your point of view

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