An flock on the snapshot dir itself is used in addition to the group dir
lock. The lock is used to avoid races with forget and prune, while
having more granularity than the group lock (i.e. the group lock is
necessary to prevent more than one backup per group, but the snapshot
lock still allows backups unrelated to the currently running to be
forgotten/pruned).
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
Attempt to lock the backup directory to be deleted, if it works keep the
lock until the deletion is complete. This way we ensure that no other
locking operation (e.g. using a snapshot as base for another backup) can
happen concurrently.
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
instead of bailing and stopping the entire GC process, warn about the
missing chunks and continue.
this results in "TASK WARNINGS: X" as the status.
Signed-off-by: Oguz Bektas <o.bektas@proxmox.com>
Used chunks are marked in phase1 of the garbage collection process by
using the atime property. Each used chunk gets touched so that the atime
gets updated (if older than 24h, see relatime).
Should there ever be a situation in which the phase1 in the GC run needs
a very long time to finish, it could happen that the grace period
calculated in phase2 is not long enough and thus the marking of the
chunks (atime) becomes invalid. This would result in the removal of
needed chunks.
Even though the likelyhood of this happening is very low, using the
timestamp from right before phase1 is started, to calculate the grace
period in phase2 should avoid this situation.
Signed-off-by: Aaron Lauterer <a.lauterer@proxmox.com>
regular chunks are only decoded when their contents are accessed, in
which case we need to have the key anyway and want to verify the digest.
for blobs we need to verify beforehand, since their checksums are always
calculated based on their raw content, and stored in the manifest.
manifests are also stored as blobs, but don't have a digest in the
traditional sense (they might have a signature covering parts of their
contents, but that is verified already when loading the manifest).
this commit does not cover pull/sync code which copies blobs and chunks
as-is without decoding them.
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
To prevent a race with a background GC operation, do not allow deletion
of backups who's index might currently be referenced as the "known chunk
list" for successive backups. Otherwise the GC could delete chunks it
thinks are no longer referenced, while at the same time telling the
client that it doesn't need to upload said chunks because they already
exist.
Additionally, prevent deletion of whole backup groups, if there are
snapshots contained that appear to be currently in-progress. This is
currently unlikely to trigger, as that function is only used for sync
jobs, but it's a useful safeguard either way.
Deleting a single snapshot has a 'force' parameter, which is necessary
to allow deleting incomplete snapshots on an aborted backup. Pruning
also sets force=true to avoid the check, since it calculates which
snapshots to keep on its own.
To avoid code duplication, the is_finished method is factored out.
Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>
And make verify_crc private for now. We always call load_from_reader() to
verify the CRC.
Also add load_chunk() to datastore.rs (from chunk_store::read_chunk())
We support using an ext4 mountpoint directly as datastore and even do
so ourself when creating one through the disk manage code.
Such ext4 ountpoints have a lost+found directory which only root can
traverse into. As the GC list images is done as backup:backup user
walkdir gets an error.
We cannot ignore just all permission errors, as they could lead to
missing some backup indexes and thus possibly sweeping more chunks
than desired. While *normally* that should not happen through our
stack, we had already user report that they do rsyncs to move a
datastore from old to new server and got the permission wrong.
So for now be still very strict, only allow a "lost+found" directory
as immediate child of the datastore base directory, nothing else.
If deemed safe, this can always be made less strict. Possibly by
filtering the known backup-types on the highest level first.
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
last_successful_backup: Returns the time of the last successful backup
group_path: Returns the absolute path for a backup_group
snapshot_path: Returns the absolute path for a backup_dir
