On Thu, May 28, 2015 4:25 pm, Gordon Messmer wrote:
On 05/28/2015 11:13 AM, Valeri Galtsev wrote:
I do not want to start "software" vs "hardware" RAID wars here
I'm not saying that hardware RAID is bad, entirely. Software RAID does have some advantages over hardware RAID, but my point has been that 3ware cards, specifically, are less reliable than software RAID, in my experience.
If I get you correctly you are saying that 3ware RAID cards are prone to hardware failures - as opposed to software RAID which is not (as it does not include hardware, so never has a hardware failures), right? No this is a joke of course. But it's the one one asked for ;-)
Now, seriously: of more than a couple of dozens of cards I used during last about 13 years not a single one died on me. Still I do not consider myself lucky. I also do not have specifically excellent conditions in a server room. Just ordinary ones. Sometimes during air conditioning maintenance temperature in the server room is higher than in our offices (once we has 96F for a couple of hours, of course this was a unique case. BTW during these 2 hours none of AMD based boxes got sick. But a few Intel ones did). So, I have no special conditions for our equipment. Boxes are behind APC UPSes, that's true, but that is sort of nothing special. I also probably should mention that all 3ware cards I used were bought new, never used by someone else. Couple of dozens is decently representative selection statistically, so I probably can't just claim myself lucky. I'm still convinced that 3ware RAID cards _ARE_ reliable.
Again, I don't know your statistics: i.e. how many did you use, how many of them died (failed as hardware). How well surge-free the power is. How well the guys who installed your cards into your boxes followed static discharge precautions (yes, even though these cards are robust, one may fry them slightly by static discharge, and they may fail - as many fried ICs they not always fail right away, but some time later, say, in a year; still as a result of static discharge). To be fair, I'm often not wearing that anti-static bracelet, but I do touch metal tars of the box, anti-static bag the card ships in etc - which is sufficient IMHO.
So, still not considering myself lucky, yet never having 3ware card die on me (out of over couple of dozens, during over 13 years, and most of the cards are in service for some 8-10 years since they originally were installed). In my book 3ware RAID cards are reliable hardware.
Valeri
++++++++++++++++++++++++++++++++++++++++ Valeri Galtsev Sr System Administrator Department of Astronomy and Astrophysics Kavli Institute for Cosmological Physics University of Chicago Phone: 773-702-4247 ++++++++++++++++++++++++++++++++++++++++