How to reset root password in Sun solaris

Boot the server with a Sun Solaris Operating System CD (I’m using a Solaris 10 CD but doesn’t matter really) or a network boot with a JumpStart server from the OBP OK prompt.

OK boot cdrom -s

or

OK boot net -s

This will boot the server from the CD or Jumpstart server and launch a single user mode (No Password).

Mount the root file system (assume /dev/dsk/c0t0d0s0 here) onto /a

solaris# mount /dev/dsk/c0t0d0s0 /a

NOTE: /a is a temporary mount point that is available when you boot from CD or a JumpStart server

Now, with the root file system mounted on /a. All you need to do is to edit the shadow file and remove the encrypted password for root.

solaris# vi /a/etc/shadow

Now, exit the mounted filesystem, unmount the root filesystem and reboot the system to single-user mode booting of the disk.

solaris# cd /

solaris# umount /a

solaris# init s

This should boot of the disk and take you to the single-user mode. Press enter at the prompt to enter a password for root.

This should allow you to login to the system. Once in, set the password and change to multi-user mode.

NOTE: Single-User mode is only to ensure that the root user without password is not exposed to others if started in multi-user mode before being set with a new password.

solaris# passwd root

solaris# reboot

This should do. You should now be able to logon with the new password set for root