My goal is to use an AuFS read only branch as another read only branch:
I've got a directory dir0
, then I make :
mount -t aufs -o br=dir2=rw:dir0=ro none dir1
This gives me
- dir0
- dir1 #read only dir0
- dir2 #write layer of dir1
I now want to use dir1
this way:
mount -t aufs -o br=dir4=rw:dir1=ro none dir3
To get
- dir0
- dir1 #read only dir0
- dir2 #write layer of dir0
- dir3 #read only dir1 (dir1 + dir2)
- dir4 #write layer of dir3
I'm using ubuntu 12.04 and this should work according to aufs-tools man page:
Any filesystem can be a branch, But some are not accepted such like sysfs, procfs and unionfs. If you specify such filesystems as an aufs branch, aufs will return an error saying it is unsupported.
But I got this error:
mount: wrong fs type, bad option, bad superblock on none, missing codepage or helper program, or other error (for several filesystems (e.g. nfs, cifs) you might need a /sbin/mount. helper program) In some cases useful info is found in syslog - try dmesg | tail or so
and dmesg
gives me
aufs test_add:231:mount[3346]: unsupported filesystem, (aufs)
Am I missing something here ? Regards, Robin