> If you take a RAID and move it from one controller to another you are a> > braver man than I am :) I was just confirming what I already thought was true. Thanks.
--Matt Ross Ephrata School District ----- Original Message ----- From: Paul Hutchings [mailto:[email protected]] To: NT System Admin Issues [mailto:[email protected]] Sent: Fri, 16 Dec 2011 10:00:25 -0800 Subject: RE: Virtualization - Sizing, hard disk config > If you take a RAID and move it from one controller to another you are a > braver man than I am :) > ________________________________________ > From: Matthew W. Ross [[email protected]] > Sent: 16 December 2011 5:03 PM > To: NT System Admin Issues > Subject: Re: Virtualization - Sizing, hard disk config > > > Plus, not all controllers that will support RAID5 will support RAID50. > > As far as I can tell, there is NO controller cross compatibility with RAID, > right? I can't use a raid 10 on an Adaptec card and expect it to cleanly > transfer to a system with a LSI card, right? > > If I'm wrong, that's excellent. But I don't think that it's true at all. > Only a software solution can be compatible across hardware (i.e.: Linux's > mdadm can handle cross-hardware raid compatibility.) > > > --Matt Ross > Ephrata School District > > > ----- Original Message ----- > From: Andrew S. Baker > [mailto:[email protected]] > To: NT System Admin Issues > [mailto:[email protected]] > Sent: Fri, 16 Dec 2011 > 05:20:10 -0800 > Subject: Re: Virtualization - Sizing, hard disk config > > > > Yes, rebuild time and overall data loss risk is worse with the RAID5 > > variants. I'd sooner do RAID6 than RAID50. > > > > Plus, not all controllers that will support RAID5 will support RAID50. > > > > * * > > > > *ASB* *http://XeeMe.com/AndrewBaker* *Harnessing the Advantages of > > Technology for the SMB market… > > > > * > > > > > > > > On Thu, Dec 15, 2011 at 10:21 PM, Ben Scott <[email protected]> wrote: > > > > > On Thu, Dec 15, 2011 at 9:20 PM, Bill Humphries <[email protected]> > > > wrote: > > > > Seems everyone assumed RAID 10. Would you not consider > > > > RAID 50 if you had 8 SAS drives and decent controller with battery > > backed > > > > cache? > > > > > > (Sanity check: RAID 50 = RAID 0 of RAID 5's = stripe of > > > stripes-with-parity. You need at least three disks for RAID 5. So > > > with 8 disks, the only configuration that uses all of them would be > > > two 4-disk RAID 5 sets, then stripped with RAID 0. Yah?) > > > > > > My take is: > > > > > > With modern disk sizes, RAID 5 can be pretty horrible during a > > > rebuild. Say you've got 8 x 600 GB. 4 x 600 = 2400 GB, raw. Lose > > > one disk, replace it, and you have to read 1800 GB to rebuild that one > > > 600 GB missing member. > > > > > > And with the large disk sizes, the chances of a double failure are > > > higher, too. Sucks to find out there's a new bad block in that > > > remaining 1800 GB. > > > > > > RAID 10 is nice and simple: At most you're doing I or O on an entire > > > single disk. Plus it's much better in terms of I/O performance. Disk > > > usage efficiency is crap at 50%, but with the low cost of storage > > > these days, that's not as big a loss as it once was. And with only 8 > > > disks, RAID 50 is only going to be 75% efficient, right? > > > > > > -- Ben > > > > > > > > > > > > > ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ > > ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~ > > > > --- > > To manage subscriptions click here: > > http://lyris.sunbelt-software.com/read/my_forums/ > > or send an email to [email protected] > > with the body: unsubscribe ntsysadmin > > ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ > ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~ > > --- > To manage subscriptions click here: > http://lyris.sunbelt-software.com/read/my_forums/ > or send an email to [email protected] > with the body: unsubscribe ntsysadmin > > > -- > MIRA Ltd > > Watling Street, Nuneaton, Warwickshire, CV10 0TU, England > Registered in England and Wales No. 402570 > VAT Registration GB 100 1464 84 > > The contents of this e-mail are confidential and are solely for the use of > the intended recipient. If you receive this e-mail in error, please delete > it and notify us either by e-mail, telephone or fax. You should not copy, > forward or otherwise disclose the content of the e-mail as this is > prohibited. > > > ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ > ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~ > > --- > To manage subscriptions click here: > http://lyris.sunbelt-software.com/read/my_forums/ > or send an email to [email protected] > with the body: unsubscribe ntsysadmin > > ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~ --- To manage subscriptions click here: http://lyris.sunbelt-software.com/read/my_forums/ or send an email to [email protected] with the body: unsubscribe ntsysadmin
