On Thu, Apr 27, 2006 at 10:04:19AM -0400, Michael Stone wrote: > >>redundancy, expandability > >What I mean by these stupid flavor words is: > >Redundancy : raid 5. > > You can get that without external storage. Yes, but some dedicated storage devices actually provide good performance with RAID5. Most simpler solutions give pretty abysmal write performance. > >>Do you > >>need the ability to do snapshots? > >Yes. > > If that's a hard requirement you'll have to eat the cost & performance > problems of an external solution or choose a platform that will let you > do that with direct-attach storage. (Something with a volume manager.) I'm wondering if PITR would suffice. Or maybe even Slony. > >>Do you want to share one big, expensive, reliable unit between > >>multiple systems? Will you be doing failover? > >Yes, and Yes. Really on one other system, a phone system, but it is the > >crux of my business and will be writing a lot of recorded phone calls. I am > >working with a storage company now to set up the failover, I want the db > >and > >phone systems to never no if the storage switched over. > > If you actually have a couple of systems you're trying to fail over, a > FC SAN may be a reasonable solution. Depending on your reliability > requirement you can have multiple interfaces & FC switches to get > redundant paths and a much higher level of storage reliability than you > could get with direct attach storage. OTOH, if the DB server itself > breaks you're still out of luck. :) You might compare that sort of > solution with a solution that has redundant servers and implements the > failover in software instead of hardware. BTW, I know a company here in Austin that does capacity planning for complex systems like this; contact me off-list if you're interested in talking to them. -- Jim C. Nasby, Sr. Engineering Consultant jnasby@xxxxxxxxxxxxx Pervasive Software http://pervasive.com work: 512-231-6117 vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461
