Re: Write cache for a SAN

From: David Ballester <>
Date: Mon, 3 Nov 2008 13:31:43 +0100
Message-ID: <>

2008/11/3 Jeffrey Beckstrom <>

> For those of you using a SAN, do you disable the write cache? I am
> concerned that if the UPS loses power thus bringing the SAN down,that writes
> to the datafiles would be lost. Oracle would think they are completed but
> never actually done.

Well, the SAN hardware should have is own batteries to avoid this. Normally they act in to ways, some vendors write the cache to the disks when the power goes off, others save the cache to a reserved disk zone ( EMC iirc ) and when the cabinet startup again, applies the pending data to real disk location, before giving access to the hosts


Received on Mon Nov 03 2008 - 06:31:43 CST

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