"Bas Groeneveld" <nospam@nospam.com.au> wrote in message
news:Pvnof.11451$V7.2999@news-server.bigpond.net.au...
> Hi
>
> This is my first post in this newsgroup and I am not sure if I have chosen
> the correct group. Please advise if a more appropriate group exists.
>
> I am planning to set up replication to a standby sql server using RYO log
> shipping in an application where a move to a backup site may be required
> if
> the main site is compromised, and back again when the situation has been
> resolved. The database size is approx 3GB (and growing) making
> transferring
> a full db backup to the standby site over a slow WAN unrealistic - hence
> log
> shipping.
>
> I am happy with the procedures to ship logs to the standby and the
> mechanism
> to bring the standby server on-line when required.
>
> In my scenario I need to transfer any changes made to the standby database
> back to the main database when the main server is brought back online - I
> am
> unsure regarding the best approach to this.
>
> The fastest way I can see is:
> 1. take a log backup from the standby server and copy this to the main
> server
> 2. restore the last main site full db backup, with all following log
> backups
> (this should bring the main server back up to the moment that the
> fail-over
> to the standby server was performed)
> 3. restore the standby log backup (which should then apply all changes
> made
> at the standby server - correct?)
> 4. bring the main database back on-line
> 5. take the backup database off-line for subsequent log shipping
>
> I am just not sure if step 3 is safe - ie can the log from the standby
> server be safely applied to the main server when switching back.
>
> Secondly, during normal operation is it safe/advisable to truncate the
> main
> database log each time the log is backed up to be shipped to the standby
> server?
>
> Thanks
>
> Bas
> --
>
> ==========================================
> Bas Groeneveld
> Benchmark Design System and Software Engineering
> PO Box 165N, Ballarat North, VIC 3350
> Phone: +61 3 5333 5441  Mob: 0409 954 501
>
>
>