If you are using CentOS rescue to fix a server and it can not automatically map/find/rebuild/whatever the directory structure correctly you may find this useful.  Using chroot after fixing everything yourself does not populate the /dev /proc and /sys directories so you need to do it yourself, if the rescue image finds the install automatically this is all done automatically as well.  Here’s what you need to run:

mount -t proc proc /mnt/sysimage/proc/

mount -t sysfs sys /mnt/sysimage/sys/

mount -o bind /dev /mnt/sysimage/dev/

chroot /mnt/sysimage