nhiggs wrote:
<<
Aim:
To deliver the required business continuity (RTO/RPO) I need to
create an "application consistent" SAN based snapshot of the Firebird
Databse disk every hour. In case of a logical error the snapshot can
be later mounted and the database restarted with a previous good version.

Solution:
My current solution is to "freeze" or "quiece" the IO to the databse
file by setting the database in backup mode. Then to flush the file
system buffers to disk using sync.exe and then create the snapshot on
the storagesystem. Afterwards the databse backup mode is turned off.
...

>>

I haven't used nbackup, so the following may be of no use, but anyway...
1.
Maybe replication would be a good solution. And switch-over should
be fairly quick.
2.
For how long can the system be unavailable after a failure? You can
probably backup a 3GB database in 10 minutes (online, without any
"freeze" or "quiesce"), but a restore might take 30 minutes. Maybe
this is too much, in particular if your database is large/huge. At
least, there is no interruption of service unless a failure happens.

Either of this should produce a copy/backup that is 100% ok.

I believe someone on this newsgroup has written about a
"almost-hot-standby" system, but I don't remember details (or the author).


--
Aage J.