Subject WG: NBACKUP and system failures AND JAVA
Author Steffen Heil

A few minutes ago, I asked some questions about nbackup at the firebird
support mailing list.
If someone here can answer, I will be very happy, too.

However, my major question on this list is, if jaybird can be used to
- Lock a database (such as nbackup -L)
- Unlock a database (such as nbackup -N)
- Detect if a database is locked?

Any hints are welcome.

Best regards,

-----Urspr√ľngliche Nachricht-----
Von: Steffen Heil [mailto:lists@...]
Gesendet: Mittwoch, 16. Februar 2011 14:06
Betreff: NBACKUP and system failures


We want to use nbackup with -L and -N to do filesystem copies (rsync
actually) of our databases.
Now, we will use this quite extensively (that is, about every 1-5 minutes).
And we are currently using firebird 2.0.4.

Therefor I have some questions:
- Is this kind of nbackup usage stable enough?
- Do we have to take any precautions about
- concurrently running gbak backups?
- power failures?
- Anything else?

Especially, what happens if the power goes down while the database is

- Will the database be consistent after reboots (forced writes is on!)?
- Will the database still be locked?
- Can the locked state be detected?
- What happens if nbackup -L is called while the database is already locked?
- Where does firebird store the information in the meantime?
- Can (where) that storage be configured?
- Is the reintegration process (as nbackup -N) itself safe w.r.t. power
failures and such?

Best regards,

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