Re: RAID1 powerloss - can parity rewrite be safely backgrounded?

2007-10-02 Thread Marco Peereboom
I have been fighting the urge of replying to this because I know I will get some yellins but here goes. The described scenario is reproducible on PERC cards when operating in a noisy environment. Bad signal integrity will always get you and eventually knock some drives offline. The described mec

Re: RAID1 powerloss - can parity rewrite be safely backgrounded?

2007-10-01 Thread Nick Holland
Steve Shockley wrote: > RedShift wrote: >> Anyone got any similar experiences with hardware RAID cards? Hardware >> RAID has always been misery for me. > > I've had two instances where older Adaptec RAID cards had a disk failure > and then reverted to a week-old copy of the data. I'm not quite

Re: RAID1 powerloss - can parity rewrite be safely backgrounded?

2007-09-28 Thread Steve Shockley
RedShift wrote: Anyone got any similar experiences with hardware RAID cards? Hardware RAID has always been misery for me. I've had two instances where older Adaptec RAID cards had a disk failure and then reverted to a week-old copy of the data. I'm not quite sure how that's possible, but hav

Re: RAID1 powerloss - can parity rewrite be safely backgrounded?

2007-09-28 Thread Nick Bender
> Anyone got any similar experiences with hardware RAID cards? Hardware > RAID has always been misery for me. I've never lost data under RAIDframe - 3 years plus using cheap SATA gear and featuring a number of unplanned hard boots and flaky air conditioning. Can't say the same for a certain hardw

Re: RAID1 powerloss - can parity rewrite be safely backgrounded?

2007-09-28 Thread RedShift
Greg Oster wrote: I worry more about a hardware RAID card forgetting its configuration after a power outage than I do about parity checking in the background :) ("What do you mean these 14 disks in this 2TB hardware RAID array are now all 'unassigned'!?!?!?!". That wasn't a fun day.) Rea

Re: RAID1 powerloss - can parity rewrite be safely backgrounded?

2007-09-28 Thread L. V. Lammert
On Fri, 28 Sep 2007, Matt wrote: > Brian A. Seklecki schreef: > > As for the suggestion of hardware raid - unfortunately this is a live > server. If I migrate it to another machine I will definitely try > hardware raid > I know it is a lot faster but would that solve the parity problem on > boot c

Re: RAID1 powerloss - can parity rewrite be safely backgrounded?

2007-09-28 Thread Brian A. Seklecki
> I know it is a lot faster but would that solve the parity problem on > boot completely? 'man bio' doesn't seem to answer that. For a variety of reasons, hardware raid controllers handle ungraceful shutdown better -- onboard batteries for the HBA's RAM/Cache, etc. Hardware RAID almost never goe

Re: RAID1 powerloss - can parity rewrite be safely backgrounded?

2007-09-28 Thread Greg Oster
Matt writes: > > As for the suggestion of hardware raid - unfortunately this is a live > server. If I migrate it to another machine I will definitely try > hardware raid > I know it is a lot faster Really? :) There is no guarantee that a hardware RAID is faster than a software RAID, or vice-v

Re: RAID1 powerloss - can parity rewrite be safely backgrounded?

2007-09-28 Thread Greg Oster
"Brian A. Seklecki" writes: > raid(4) hasn't been touched in a while (years), so short answer: No. > > NetBSD is still actively committing to it, though, and has functional > background parity recalculation. Just to be clear here: the background parity checking in NetBSD as of today is function

Re: RAID1 powerloss - can parity rewrite be safely backgrounded?

2007-09-28 Thread Matt
Brian A. Seklecki schreef: raid(4) hasn't been touched in a while (years), so short answer: No. NetBSD is still actively committing to it, though, and has functional background parity recalculation. I understand there is interest in replacing RAIDFrame instead of resynchronizing the subtree.

Re: RAID1 powerloss - can parity rewrite be safely backgrounded?

2007-09-27 Thread Brian A. Seklecki
raid(4) hasn't been touched in a while (years), so short answer: No. NetBSD is still actively committing to it, though, and has functional background parity recalculation. I understand there is interest in replacing RAIDFrame instead of resynchronizing the subtree. In the mean time, find a

Re: RAID1 powerloss - can parity rewrite be safely backgrounded?

2007-09-27 Thread Rob
On 9/25/07, Matt <[EMAIL PROTECTED]> wrote: > I'm running a RAID1 mirror on OpenBSD 4.1 (webserver) > On a power failure the parity becomes dirty and needs rewriting, which > results in > 1.5 hours 'downtime'. > Is it safe to background this in /etc/rc or is that a no-no? > > I found a reference th

RAID1 powerloss - can parity rewrite be safely backgrounded?

2007-09-25 Thread Matt
I'm running a RAID1 mirror on OpenBSD 4.1 (webserver) On a power failure the parity becomes dirty and needs rewriting, which results in > 1.5 hours 'downtime'. Is it safe to background this in /etc/rc or is that a no-no? I found a reference this was possible/safe on-list but it was a) 2003 and