One method to recover a lost root password
derekj at tourneo.com
Fri Mar 16 21:04:52 UTC 2007
How I recovered a lost root password in FreeBSD
This was on a CyberGuard LX firewall, running version 4.2 BSD
Luckily I did know one user name and it had no password.
Using the boot CD, pick option 4 for single use mode
going through the country and keyboard
going to the repair mode with CDROM/DVD option off the install menu,
using the "live" CDROM filesystem gave me a root prompt Fixit#
now mounting the hard drive, in my case /dev/ad0s3a
mount /dev/ad0s3a /mnt
now edit the master password file
on the root line, delete all characters between the first two :: to remove
the root password altogether.
hence ending up with
root::0:0::00:Charlie &:/root:/bin/csh or something similar
save the file
now change permissions, but look at them first, make a note so you can put
them back to the correct setting later
chmod 777 /mnt/etc
chmod 666 /mnt/etc/master.passwd
remove the CD and reboot the original system.
For some reason my older FreeBSD version 4.3 filesystem did not like being
mounted onto a FreeBSD 6.1 install CD
Hence on reboot it made me do a manual fsck
Then another reboot
Now login as a user, cgadmin in my case
get a prompt and run
This rebuilds the secure password database
Now get another getty - say Alt-F4 and login as root
Reboot if you like, set yourself a new root password and write it down this
I prefer a label on the bottom of the box, because if you have got this
access, you can crack the password.
Now don't forget to set the file security back to where it was
chmod 755 /etc
chmod 600 /etc/master.passwd
Hope you enjoyed the day.
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