How to Root Nexus S on Android 2.3.4

As Google has released Android 2.3.4 update for Nexus S mobile devices, now if you want to get root access to your device then following guide will help you to do that.

Root Nexus S on Android 2.3.4

Step-1
Download SU rooting file
Step-2
Attach your Nexus S to your system with USB and copy the downloaded SU file to your phone’s directory

Step-3
Hold down Power + Volume down buttons to restart your phone into recovery mode
Step-4
When your device will be in recovery mode, select the mounts and storage from Mount/System and Mount/data
Step-5
Navigate to main menu, from SD card option find Install Zip file
Step-6

Select your copied SU file and select Ok
Step-7
Flashing process will start, on completion just restart your mobile
Done! your Nexus S on Android 2.3.4 is rooted now.
see original post here 

http://www.rizwanashraf.com/2011/05/02/how-to-root-nexus-s-on-android-2-3-4/