Mounting volume to non-empty directory 1

[fugtruck]

I have my root filesystem on /dev/sda1. I want to mount another volume, sdb1, to the /usr directory. Once I do that, how would I go about deleting the contents from the /usr directory on sda1 other than booting the computer to a rescue disk (the computer is in a remote location and there is nobody to put a disk in for me)?

 

[SamBones]

You can access the files under the mount point without unmounting the filesystem over them. See this arcticle...

http://www.sun.com/bigadmin/content/submitted/peek_mount_points.jsp

It's Solaris specific, but the technique should work for Linux too.

 

[fugtruck]

Wow, I hadn't thought about doing that. Nice!

 

[ady2012]

Backup or rsync exist /usr and rename /usr to /usr1.
Next mount /dev/sdb1 to /usr and restore all files

 

[3t0n1c]

Try this:

mv /usr /usr_old
mkdir /usr
mount /dev/sdb1 /usr

Also, don't forget to edit your fstab file to reflect the changes.

Good luck!