Backup fails: checkPreconditions errored with code 1 message

[nichu42]

Hi there,

It's the second day now that the backup fails with this error message.
The app ID points to Mastodon, which is running fine as far as I can tell.
I am running v8.0.6 with backups to Hetzner Storage Box via sshfs, but I understand correctly, it's not even getting to the upload part.

checkPreconditions errored with code 1 message Command failed: du -Dsb --exclude=*.lock --exclude=dovecot.list.index.log.* /home/yellowtent/appsdata/c5d30482-9837-4fdb-8c21-04ef653d691c du: cannot access '/home/yellowtent/appsdata/c5d30482-9837-4fdb-8c21-04ef653d691c/data/system/cache/media_attachments/files/113/345': No such file or directory du: cannot access '/home/yellowtent/appsdata/c5d30482-9837-4fdb-8c21-04ef653d691c/data/system/cache/media_attachments/files/113/346/860': No such file or directory du: cannot access '/home/yellowtent/appsdata/c5d30482-9837-4fdb-8c21-04ef653d691c/data/system/cache/media_attachments/files/113/346/861': No such file or directory du: cannot access '/home/yellowtent/appsdata/c5d30482-9837-4fdb-8c21-04ef653d691c/data/system/cache/media_attachments/files/113/346/865': No such file or directory du: cannot access '/home/yellowtent/appsdata/c5d30482-9837-4fdb-8c21-04ef653d691c/data/system/cache/media_attachments/files/113/346/867': No such file or directory du: cannot access '/home/yellowtent/appsdata/c5d30482-9837-4fdb-8c21-04ef653d691c/data/system/cache/media_attachments/files/113/347/542': No such file or directory du: cannot access '/home/yellowtent/appsdata/c5d30482-9837-4fdb-8c21-04ef653d691c/data/system/cache/media_attachments/files/113/347/545': No such file or directory du: cannot access '/home/yellowtent/appsdata/c5d30482-9837-4fdb-8c21-04ef653d691c/data/system/cache/media_attachments/files/113/347/541': No such file or directory du: cannot access '/home/yellowtent/appsdata/c5d30482-9837-4fdb-8c21-04ef653d691c/data/system/cache/media_attachments/files/113/347/556': No such file or directory du: cannot access '/home/yellowtent/appsdata/c5d30482-9837-4fdb-8c21-04ef653d691c/data/system/cache/media_attachments/files/113/347/548': No such file or directory du: cannot access '/home/yellowtent/appsdata/c5d30482-9837-4fdb-8c21-04ef653d691c/data/system/cache/media_attachments/files/113/347/550': No such file or directory du: cannot access '/home/yellowtent/appsdata/c5d30482-9837-4fdb-8c21-04ef653d691c/data/system/cache/media_attachments/files/113/347/553': No such file or directory du: cannot access '/home/yellowtent/appsdata/c5d30482-9837-4fdb-8c21-04ef653d691c/data/system/cache/preview_cards/images/001/263': No such file or directory du: cannot access '/home/yellowtent/appsdata/c5d30482-9837-4fdb-8c21-04ef653d691c/data/system/cache/preview_cards/images/001/278': No such file or directory

[nebulon]

This is unfortunately a known issue with the linux du command. It happens, when a file gets removed while it is trying to calculate the size of a folder structure. This happens with apps which frequently do file operations while the backup tries to calculate the expected size of the backup.

For some known filetypes, we already use the --exclude argument, but since those files here do not have an extension this is tough.

The proper fix will be a custom implementation of du where we can handle such cases, as we only need a rough size estimation here.

Until we have that, I guess the app needs to be stopped for the backup or the backup retried until it hits a point where the files do not change mid-way.

[nichu42]

For some reason, this never happened before and now happens every night. I cannot stop the (public) Mastodon instance and wait for the backup to complete. So I am patiently waiting for the fix.

[girish]

Fix is in - https://git.cloudron.io/platform/box/-/commit/6407d795ed8f6058d7b18aca8f39295abf6f745a . Should be in next release. The new release is going through e2e tests, so we will get it out asap.

[nichu42]

It looks like the problem is indeed gone with 8.1
Thank you!