Re: Cluster and WriteBack Caching

I am gonna disagree here... Sort of. Never use Write caching on local disk
controllers in a cluster. However, Internal SAN write caching is a good
thing that allows significant performance improvements. This is assuming
that the SAN vendor has a very strong data protection (batteries,
de-staging, mirrored cache, etc.) design.

--
Geoff N. Hiten
Senior Database Administrator
Microsoft SQL Server MVP

"Mike Epprecht (SQL MVP)" <mike@xxxxxxxxxxxx> wrote in message
news:equSLKrnFHA.576@xxxxxxxxxxxxxxxxxxxxxxx
> Hi
>
> Yes. Write caching can not guarantee that the data is on disk if the
> server dies. In that case, your "high availability" solution could turn
> into a "no-availability" solution as you will probably have database
> corruption after the failover.
>
> Read caching, that is OK, but never write caching.
>
> Regards
> -------------------------------
> Mike Epprecht, Microsoft SQL Server MVP
> Zurich, Switzerland
>
> IM: mike@xxxxxxxxxxxx
>
> MVP Program: http://www.microsoft.com/mvp
>
> Blog: http://www.msmvps.com/epprecht/
>
> "JT" <Jthayer@xxxxxxxxxxxxx> wrote in message
> news:95F802D0-13AE-4A7B-B17B-59FE8A1FDDB6@xxxxxxxxxxxxxxxx
>> Hi,
>> I have a 2 instance sql failover cluster on two nodes. Currently, write
>> and
>> read back caching are enabled on all disks in the SAN. Could this lead
>> to
>> problems? Thanks.
>> --
>> John
>
>


.

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