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Generate Random Passwords

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

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`

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
49

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
15

-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

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 if=/dev/urandom count=200 bs=1 2>/dev/null | tr "\n" " " | sed 's/[^a-zA-Z0-9]//g' | cut -c-16
openssl rand 6 -base64
2011-10-05 14:24:41
User: Le_Jax
0

just change 6 to 9 or 12 or more (multiple of 3) to have bigger password

Know a better way?

If you can do better, submit your command here.

What others think

makepasswd
Comment by SiNiESTrO 391 weeks ago

Works great! Thanks!

Comment by viniciusfs 391 weeks ago

That's mkpasswd, wich waits for user input:

mkpasswd

Password:

Comment by Blackbit 389 weeks and 6 days ago
pwgen
Comment by bwoodacre 367 weeks and 4 days ago

Your point of view

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