Writings Photos Code Contact Resume Me
Generate random passwords under GNU/Linux...
Submitted by msameer on Sat, 11/02/2006 - 1:30am.

Well, I want to generate random passwords for people I give subdomains.

Since creating the subdomain involves a lot of steps, I decided to automate it a bit.

And since I only install the most needed things on the server, I decided to create a small script to generate the random password for me as I don't feel like installing a password generator.

dd if=/dev/random count=10 bs=1 | hexdump  | cut -d \  -f 2-| head -n 1 | tr -d " "

Now the only 2 problems with the above script are:
1) No upper case letters.
2) No special characters.

I don't really think that the above problems are fatal since the user will change the password after that to something stupid, Why ? Because users are idiots, They are not as smart as me ;-)

Syndicate content  digg  bookmark

Submitted by conceptor@eglug.org on Sat, 11/02/2006 - 5:24am.

you can limit how man uppercase characters and how many spacial characters needed on your passwd

$ makepasswd --char=10

Submitted by msameer on Sat, 11/02/2006 - 12:44pm.

I don't want to install additional things.

For the sake of learning, I'll have a look at its source code to see how it's done ;-)

Submitted by mrdvt92 (not verified) on Sat, 22/07/2006 - 7:16am.

Try somthing like this and you can pick what chars you want by editing the sed.

dd if=/dev/urandom count=200 bs=1 2>/dev/null|tr "\n" " "|sed 's/[^a-zA-Z0-9]//g'|cut -c-16

Submitted by Anonymous (not verified) on Sat, 05/01/2008 - 6:07pm.

Here is what I came up with:

head -c 200 /dev/urandom | tr -cd '[:graph:]' | head -c 8

Submitted by Anonymous (not verified) on Sat, 02/02/2008 - 1:21am.

Why head -c 200 /dev/urandom
instead of simply cat /dev/urandom?

Submitted by msameer on Sat, 02/02/2008 - 4:53am.

try it ?

Submitted by Sharki (not verified) on Mon, 03/03/2008 - 8:50pm.

Use md5sum for better passwords:


dd if=/dev/urandom count=128 bs=1 2>&1 | md5sum | cut -b-10

Note '2>&1', this makes sure dd's stderr output is piped to md5sum, instead of your terminal.

Post new comment
The content of this field is kept private and will not be shown publicly.
  • Allowed HTML tags: <a> <b> <dd> <dl> <dt> <i> <s> <li> <ol> <u> <ul> <br> <br />
  • You may post code using <code>...</code> (generic) or <?php ... ?> (highlighted PHP) tags.
  • You can use BBCode tags in the text, URLs will automatically be converted to links.
  • Lines and paragraphs break automatically.
  • You may write mixed Arabic and English freely, line direction will be computed automaticaly

More information about formatting options