Friday, March 23, 2012

Log Shipping Question

While reviewing our log shipping setup, I noticed we backup, ship and restore
logs from 7am-7pm. We also perform a full backup at 9pm.
My question is this: Will the transaction backup at 7am pick up
transactions since the last transaction log backup at 7pm or since the full
backup at 9PM. Are we losing 2 hours of transactions?
SqlServer2005 SP2.
Thanks.
Ron
Full and transaction logs are almost completely independent. Almost means
that you have to have a full backup to initialize the log chain. After
that, a full backup has no impact on the transaction log backups. For
example, if last night's backup was bad, you can go back two days and
restore logs up to today. As a side effect, full backups do not mark any
part of the transaction log as inactive so transaction log backups are
necessary to truncate a log when in full recovery mode.
Each log backup consists of the completed and checkpointed transactions
since the last transaction log backup. Once these transactions are backed
up, the log space is marked inactive and can be reused.
Geoff N. Hiten
Senior SQL Infrastructure Consultant
Microsoft SQL Server MVP
"Ron" <Ron@.discussions.microsoft.com> wrote in message
news:4A35A3CB-E733-4AE5-9780-1DACB82C9ABE@.microsoft.com...
> While reviewing our log shipping setup, I noticed we backup, ship and
> restore
> logs from 7am-7pm. We also perform a full backup at 9pm.
> My question is this: Will the transaction backup at 7am pick up
> transactions since the last transaction log backup at 7pm or since the
> full
> backup at 9PM. Are we losing 2 hours of transactions?
> SqlServer2005 SP2.
> Thanks.
> Ron

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