On 27 Mar 2015 01:24:06 -0700, "hugo.larson@... [firebird-support]"
<firebird-support@yahoogroups.com> wrote:

> We have a POS application using Firebird 2.5.3 together with JayBird on
> about 300 sites.
>
> The applications runs nbackup several times everyday. It has happened
> several times on several sites that nbackup fails with following

exception:

> org.firebirdsql.jdbc.FBSQLException: GDS Exception. 335544351.
> unsuccessful metadata update
> Database is already in the physical backup mode
>
> What happes after this is that all database changes from that point get
> stored in the .delta file.
>
> The soulution i found is to make a full gbak and restore it.

You don't need to restore from a gbak backup, executing ALTER DATABASE END
BACKUP as sysdba (see
http://www.firebirdsql.org/file/documentation/reference_manuals/reference_material/html/langrefupd25-ddl-database.html#langrefupd25-alter-db
) should be enough to have the delta file merged back into the database
and ending physical backup mode.

> The is serious nbackup issue which causes problem for the database in
> general.
> The only way to discover this problem is to look after a .delta file or
> attempt another run nbackup again.
> I dont think it's database corruption or disk problem because it has
> happen too often and everything works fine after the restoring from

gbak.

The question is whether this is an actual nbackup problem, or if Jaybird
does something wrong with its nbackup implementation causing the backup to
not end correctly. Do you have a reproducible case? Have you checked
whether the previous backup actually ended, or ended correctl?

> I have a copy of such corrupted database if it's interesting.

Not sure if it is: it sounds like the backup mode wasn't completed, and
that is not a corruption.

Mark