2011-05-27 10:21:03 +0200, Andreas Philipp: [...] > > What do those top-level IDs mean by the way? > The top-level ID associated with a subvolume is NOT the ID of this > particular subvolume but of the subvolume containing it. Since the > "root/initial" (sub-)volume has always ID 0, the subvolumes of "depth" > 1 will all have top-level ID set to 0. You need those top-level IDs to > correctly mount a specific subvolume by name. > > # mount /dev/dummy -o subvol=<subvolume>,subvolrootid=<top-level ID> > /mountpoint > > Of course, you do need them, if you specify the subvolume to mount by > its ID. [...]
Thanks Andreas for pointing that subvolrootid (might be worth adding it to https://btrfs.wiki.kernel.org/index.php/Getting_started#Mount_Options BTW). In my case, on a freshly made btrfs file system, subvolumes have top-level 5. (and neither volume with id 0 or 5 appear in the btrfs sub list). All the top-levels are 5, and I don't even know how to create a subvolume with a different top-level there, so I wonder how that subvol that I had created with btrfs sub snap data snapshots/2011-03-30 ending up being a subvolume with ID 285 that doesn't appear in the "btrfs sub list" and contains a subvolume of "path" "data" in there (with its top-level being 285). All the other subvolumes and snapshots I've created in the exact same way are created with a top-level 5 and have an entry in "btrfs sub list" and don't have subvolumes of their own. -- Stephane -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
