diaster recovery for linux

boot from live cd

mount the partition

mv etc etc.ORG

mv sbin sbin.ORG

mv usr usr.ORG

mv var var.ORG

install the linux and keep all the mount point, do not format the partition

after installation

Restore account

cp /etc.ORG/passwd /etc; cp /etc.ORG/group /etc; cp /etc.ORG/shadow /etc; cp /etc.ORG/gshadow /etc

cp -a /etc.ORG/httpd /etc     <– any service config file you want to restore