Can I mount single folders in a 2nd HD to a master folder I have on my main HD?

Question

Essentially I have a server setup as a media device running MuthTV for my main tv off the Ubuntu comp and then I have several other PC's in the house which connect to the shared folder of my server to watch from the other TVs.

To make things look nice and organized within both Myth and my folders I divided stuff up as such, a main Video folder which is shared and within it a Movie, TV, Stand Up, Music Videos etc.. I previously ran out of space on the main HD and bought a new one, what I did then was transfered the entire Movie folder to the new HD and mounted it in the Video folder as 'Movies' essentially not messing with my organizational scheme.

However, now its my TV folder which is almost too big to sit on a HD by itself without allowing for room to grow. So what I want to do now is get another HD and instead of mounting the entire HD in the Video folder somewhere, to put it elsewhere and just mount folders I have put in the new HD to the TV folder.. essentially meaning I could have 'The Big Bang Theory' appear in my TV folder but actually be located on the new HD.. I also would like to have many different shows folders come off that new HD essentially mounting many folders to that TV folder.. if that makes sense. I am not sure mounting is the word I am looking for for how to accomplish this but I wasn't sure what other methods there were. Thanks in advance.

Answer 1

Each disk partition has an identifier, i.e. /dev/sda1, /dev/sdb2 and so on. You can mount, or map, any of these to any "point" on the filesystem, point meaning a "directory". So what you want can be achieved no problem.

Say the new hard disk you add is /dev/sdc1 (I'm thinking since you have 3 hard disks already, but please change if your drive letter is different). In a nutshell, you'd have to do this:

1. Mount the new device manually in /mnt: sudo mount /dev/sdc1 /mnt
2. Copy stuff from the old folder to the new device: cp -a /Videos/TV/* /mnt
3. Move the old folder out of the way (don't delete yet, until you're sure it's all working well): mv /Videos/TV /Videos/old-TV
4. unmount new device: sudo umount /mnt
5. Create mount point (empty directory to which the new device will be attached): mkdir /Videos/TV
6. mount new device to mount point: sudo mount /dev/sdc1 /Videos/TV

If you now go to /Videos/TV you should see all the files you have in the new device. Also, if you issue the df -h command, you should see a list of devices, space usage and mount points.

Note that in order to make step 6 permanent, you need to add an entry in /etc/fstab:

/dev/sdc1 /Videos/TV  ext4  defaults  0  0