When root partition is full on ESX host

I had been in a strange situation when upgrade of ESX host was failing. It was giving me all kind of wired messages.
This host had NFS mount where I had placed my swap files. Host was suppose to moved from one location to other location. Person who powered off did not realize that it had NFS mount. When ESX host was powered on different location it started giving me error message that it is still trying to do NFS mount (ALT+F12 log).

I was also getting error message "Configuration changes were not saved successfully during previous shut down" . The reason for this was ,root file system was full (Please dont ask me why , we have many admin)

I used "esxcfg-nas " command to delete that mount. But still my root partation getting filled message didnot resolved.

So I thougth of running following command to find out what files are above 10GB.

find / -size +10240000c -exec du -h {} \; | less


I found that some one has stored ISO file under /vmimage . :)

Deleted thoso ISO and I was able to upgrade my host to 3.5U4