--On August 29, 2007 1:03:53 PM -0700 Mike Bird <mgb-debian@yosemite.net> wrote:
On Wednesday 29 August 2007 03:26, Michelle Konzack wrote:2) Does anyone know, where I can get complete Server which fit my needs? It does not need very much memory (~2 GByte) and need only a small CPU since its FileServer usage, but need 3Ware 8-channel Controller.Although 3Ware website and 9xxx product data sheets still claim support for JBOD, once you read the huge user manual you find that JBOD support was discontinued in a firmware "upgrade". Single disk mode is available but your data is still hidden behind the 3Ware layer and unavailable without paying the 3Ware ransom. Which means you have to go out and buy another overpriced 3Ware and keep it in a cupboard so you can recover your data when the first controller dies. Google will also show you many instances over the years of people finding their 3Ware running at a tiny faction of advertised speed. Never again 3Ware! Buy an inexpensive OEM controller and use software RAID. Much more reliable and often faster.
MDRAID certainly isn't reliable in a huge number of failure cases. It causes the machine to OOPS/lock up. Or even lose data. MDRAID is also very difficult to administer, offering only (depending on your version) mdadm or raid* tools. mdadm is rather arcane. simple operations are not well documented, like, how do i replace a failed drive? or start a rebuild? there's no 'rebuild drive' it's completely NON automated either. meaning it always takes user intervention to recover from any failure. a single I/O error causes MDRAID to mark the element as failed. it does not even bother to retry. MDRAID is also incapable of performing background patrolling reads, something i think even 3Ware does. MDRAID RAID5 sets are non-bootable. Something you get from any hardware raid, evne 3Ware. My money lately has been on LSI's cards. 3Ware is a good second choice too. the newer ICP* modelled ICP controllers are shit (as opposed to the pre intel/adaptec GDT* series which are rock solid).
I can never recommend any software RAID for anything other than simple mirrors, and then, always, with the caveat that it will be a bitch to fix if things go wrong, you probably won't lose data, but getting a software raid running again is often arcane, especially with MDRAID and it's frequent inability to correctly identify a failed drive (sometimes the fault of the SATA controller mind you). BSDs vinum is little better in these regards. And god forbid you lose your boot drive and have forgotten to keep all the boot blocks on your spare properly updated. you also have to manually intervene and reorder drives in that case, something hardware raid, any hardware raid, will transparently cover.
--Mike Bird -- To UNSUBSCRIBE, email to debian-isp-REQUEST@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmaster@lists.debian.org
-- Michael Loftis Modwest Operations Manager Powerful, Affordable Web Hosting