Hi,

> > Why do you need a localhost prefix? NBackup is expected to work fine
> > without it, regardless of the TCP port of the FB server.
>
> I need TCP, because I don't want 'direct access to the database file'
> as I understand that this kind of access is not multi-thread safe. All
> my database clients are connected to the database through TCP
> (localhost).

NBackup only works by using direct access (via the server), you can
safely continu working on the database. Thread safety has nothing
to do with it.

> > > 3. Is full nbackup database dump (-B0 option) compatible with the gbak
> > > dump and vice versa?
> >
> > Nope, they're completely different beasts.
>
> Pity, but I understand that gbak is doing some 'database cleaning'
> while performing backup and nbackup does not. If I start to use
> nbackup for regular backups, is there any other tool that can be used
> to 'maintain compact' database?

gbak will not "maintain compact" the database either, it -can- clean
up the garbage, but the database file(s) will stay the same size.

> - when making full backup, seems that whole database file is copied to
> the backup file, prior to this nbackup seems to lock database with
> ALTER DATABASE BEGIN BACKUP thus allowing somewhat safer copy...

Not a "somewhat safer copy", this functionality was -exactly- created
for NBackup.

> - when restoring database, original database file must not exist, you
> have to delete it manually
> - when making incremental backups u are never exactly sure what is
> last full backup file from which incremental backup is done. I
> recently found that you can find last full backup in the
> RDB$BACKUP_HISTORY syste table, sort by date and find last backup with
> level 0
> - only thing that I can say is that I've tested nbackup on 'live
> database with connected clients' and it seems to work without error
> and very fast.

Which is what is was created for.

> - with all these in mind and with warning that nbackup versions prior
> to 2.1.1 can cause database deadlock probably I should give up on
> incremental backups for firebird database until nbackup becomes more
> stable.
>
> Final question:
> Does anybody actually use nbackup for database backups? Anyone has
> practical experiences with this tool?

Martijn Tonies
Database Workbench - tool for InterBase, Firebird, MySQL, NexusDB, Sybase
SQL Anywhere, Oracle & MS SQL Server
Upscene Productions
http://www.upscene.com
My thoughts:
http://blog.upscene.com/martijn/
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