On Wed, Sep 11, 2002 at 03:46:43PM -0700, sean.upton@uniontrib.com wrote:
I strongly considered this option at one time with a shared DAS/RAID between my primary and secondary ZSS. I never ended up doing this because of concerns.
[...]
It really seems like replication is really a less brittle option (though how much less brittle, I'm not sure).
Hear, hear... Besides, you still have a single point of failure: your SAN system. OK, it's expensive and may thus fail less, but then you might buy an expensive system to begin with ;-) Another experience I had with such semi-high-end thingies is: if you haven't (some access to) experience with this very configuration, unexpected problems tend to crop up, thus eating up the advantage you thought to have. You are dealing with a more exotic system, with a smaller installed base, remember. You better know you understand very well how it works (or you have access to someone who does). Don't believe what marketing says -- those guys are in bed when one of your SCSI disks in the array fails and the RAID controller thinks it hasn't a hot spare and it'd better shut down the system (I had this one too -- luckyly I don't sell myself as hardware guy ;-)
Though not committed at this point, for a big project I am working on, I am strongly considering use of DirectoryStorage and its snapshot capabilities for low-tech replication (via find+cpio+nfs) to try and minimize issues I might face similar to #2 and #3 if I had chosen FileStorage.
I'd tend myself too to low-tech replication solutions -- in spite of the issues they present. Besides, if the systems are far apart, they still work if one of the buildings catches fire =:-0 Cheers -- tomas