have /home/user/Downloads (and other user folders) on a different partition

Question

I recently got an SSD. I use it to store my / as well as my /home directories (on different partitions).

For each user, I would like to have most of their folders on my big RAID-1 with 2 hard drives (I'm talking about /home/<user>/Downloads, /home/<user>/Music, /home/<user>/Documents, etc. to make this more clear).

First I thought about symlinks, but I think this wouldn't work, as the whole home-directories should be encrypted with ecryptfs.

So, how can this be achieved?

Answer 1

You could create an encrypted partition on the RAID, and give each user a directory there (just like /home/user with respect to user/group ownership), and symlink the offending directories in there. I don't know offhand if such a setup will work with all users of those directories, or if there is a way to make the user's Downloads just really be at /home2/user/Downloads by some overall or user-specific configuration.

Answer 2

I found a solution. Yet it is not perfect, but I think it can be improved. Basically I did what @rcoup suggested here: https://askubuntu.com/questions/103835/securely-automount-encrypted-drive-at-user-login/165451#165451

On debian for some reason mount.ecryptfs_private is in /sbin/. One can access mount.ecryptfs_private without root-privileges, however instead of

mount.ecryptfs_private extra

I had to use

/sbin/mount.ecryptfs_private extra

I wrote a script to mount every folder in home seperately, however that's maybe not the best way to do it, as everytime I move a file (e.g. from Downloads to Music) this process takes some time. Maybe it would be better to use /sbin/mount.ecryptfs_private to just mount one folder and use symlinks then.