Actually, I have noticed that most internal RAID controllers tend to be pretty brain dead when it comes to RAID-10 (actually RAID 0+1), doing a round-robin read down both paths which results in *slower* I/O than a single disk (in a 4-disk RAID-10 anyway). I actually did a head-to-head comparison, and with 4 disks, RAID-5 is faster than RAID-10 on most controllers. The only exception is large, sequential writes (cache handles everything else), and with something like the NBU catalog, your large I/Os are reads which are always faster on RAID-5 anyway, given the same number of disks.
So, for my backup master, I have six internal drives. The first two are a mirror (RAID-1) for OS. Note: DON'T put swap on RAID-5. ...and the last four are a RAID-5 for catalog. ----Original message---- Date: Mon, 7 May 2007 11:42:25 -0400 From: "Paul Keating" <[EMAIL PROTECTED]> Subject: Re: [Veritas-bu] Hardware Recommendations for new setup To: <veritas-bu@mailman.eng.auburn.edu> Message-ID: <[EMAIL PROTECTED] nada.ca> Content-Type: text/plain; charset="utf-8" Will it be a master/media, or just a media with the Master at your Main site? Makes a bit of a diff, since a Master will have much more IO to the local catalog. With that much data, I would have no problem going with the T2000 with the 4 disks. Create a RAID10 RG, and cut it up into slices for OS and NBU. With striped mirrors, you should have any IO issues. You could probably make due with two separate RAID1 RGs, once for OS and one for /opt/openv/. The V240 has MORE than ample PCI IO for that amount of data, but if the T2000 is cheaper, I'd go that way. If/when you eventually need more performance for the catalog, you can put it on FC-SAN disk, or an external FC array. Paul -- Joe Royer / SysAdmin / Digital Motorworks / 512-692-1028 This message and any attachments are intended only for the use of the addressee and may contain information that is privileged and confidential. If the reader of the message is not the intended recipient or an authorized representative of the intended recipient, you are hereby notified that any dissemination of this communication is strictly prohibited. If you have received this communication in error, please notify us immediately by e-mail and delete the message and any attachments from your system. _______________________________________________ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu