I have made several personal configuration changes to a Raspbian Wheezy install (more secure ssh, personal configurations, etc). It's been a couple weeks since I last touched it, and I completely forgot the password to login. What should I do?
Right off the bat, let me say that there is not a way to recover a password (without some actual cracking/hacking which I don't know how to do). Resetting your password is your best bet.
So the first step will be to determine if you have any way to log in to the Raspbery Pi.
If you're able to log in with a user that has 'sudo' rights (this includes SSH... perhaps you have keys set up properly but forgot the actual user password, which I ran in to), simply typing:
should prompt you to create a new password (without having to enter your current password).
Another option would be to run the starting config and change the password that way.
If you're completely locked out, you can try the technique mentioned here, though I didn't have any success with the strategy. It just kept me from finishing booting up the RPi.
I haven't found any good techniques to enable root access period (putting the conversation of why you'd even want to do that aside :) ), let alone if you can't log in. Somebody can correct me if I'm wrong.
Hopefully this will save you from blowing away an image with a fresh one. If this saves one person, figure it's worth the time to post :)
Mount the SD card, go into the file system, and edit
/etc/passwd. Find the line starting with "pi" that begins like this:
Get rid of the x; leave the colons on either side. This will eliminate the need for a password.
You probably then want to create a new password by using the
passwd command after you log in.
If you have physical access to the pi, look at these instructions. Essentially, mount the SD card using a different machine and edit
cmdline.txt to include (at the end)
init=/bin/sh. Then, run the following commands:
mount -o remount,rw / passwd pi (enter a new password) sync exec /sbin/init
As Jamie Cox commented in one answer and what actually worked for my problem, you might want to change the password for the pi user, so type
sudo passwd pi
otherwise you are just changing the password for root.