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generate random password

Terminal - generate random password
tr -dc 'a-zA-Z0-9' < /dev/urandom | head -c10
2009-12-01 14:22:20
User: Phil
Functions: head tr
-1
generate random password

A slightly shorter version. Also doesn't put a return character at the end of the password

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives
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

openssl rand -base64 6
cat /dev/urandom | env LC_CTYPE=C tr -dc a-zA-Z0-9 | head -c 16; echo
2014-02-05 15:04:07
User: yakovlev
Functions: cat env head tr
1

Feel free to put this in your ~/.profile:

random(){ cat /dev/urandom | env LC_CTYPE=C tr -dc $1 | head -c $2; echo; }

Then use it to generate passwords:

random [:alnum:] 16

Or DNA sequences:

random ACGT 256
cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 10 | sed 1q
env LC_CTYPE=C tr -dc "a-zA-Z0-9-_\$\?" < /dev/urandom | head -c 10
2011-02-22 17:09:44
User: aerickson
Functions: env head tr
0

Prepending

env LC_CTYPE=C

fixes a problem with bad bytes in /dev/urandom on Mac OS X

Know a better way?

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