Hi list,

I'm sorry to come back with my problem. I'm pretty sure it's not
dovecot-related, but can someone help me to bring some debug information
to Ceph developers ?

For example, how writes are handled in Dovecot, and what kind of
corruption it is according to error messages ?

On 13/12/2017 16:19, Florent B wrote:
> Hi,
>
> I use Dovecot (last released version), 2 backends and 1 director, each
> user account handled by a single assigned backend.
>
> I use CephFS filesystem for messages (FUSE client).
>
> Since Ceph upgrade from Kraken to Luminous, I have a lot of erreurs
> "Error: Corrupted dbox file" on a single (large) mail account.
>
> I know the problem seems to come from Ceph, but maybe someone here can
> help me diagnose the situation.
>
> The error is exactly : EOF reading msg header (got 0/30 bytes)
>
> Dovecot backends are configured like this :
>
> mmap_disable = yes
> mail_fsync = optimized
> mail_nfs_storage = no
> mail_nfs_index = no
> mdbox_rotate_size = 12M
>
> CephFS supports file locking, and 2 backends never write the same file
> because each user is assigned to a backend.
>
> Did you ever see this problem with others FS maybe ?
>
> It seems problem disappeared when I disable pagecache for the Fuse mount.
>
> Thank you for your help.
>
>