On 03/07/2011 09:00 AM, Nico Kadel-Garcia wrote:
On Sun, Mar 6, 2011 at 10:07 PM, Charles Polishercpolish@surewest.net wrote:
https://secure.wikimedia.org/wikipedia/en/wiki/Fakeraid#Firmware.2Fdriver-ba... covers fake RAID.
Ouch. That was*precisely* why I used the 2410, not the 1420, SATA card, some years back. It was nominally more expensive but well worth the reliability and support, which was very good for RHEL and CentOS.
I hadn't been thinking about that HostRaid messiness because I read the reviews and avoided it early.
Here's the latest info which I'll share ... it's good news, thankfully.
The problem with terrible performance on the LSI controller was traced to a flaky disk. It turns out that if you examine 'dmesg' carefully you'll find a mapping of the controller's PHY to the "id X" string (thanks to an IT friend for that tip). The LSI error messages have dropped from several thousand/day to maybe 4 or 5/day when stressed.
Now the LSI controller is busy re-syncing the arrays with speed consistently over 100,000K/sec, which is excellent.
My scepticism regarding SMART data continues ... the flaky drive showed no errors, and a full test and full zero-write using the WD diagnostics revealed no errors either. If the drive is bad, there's no evidence that would cause WD to issue an RMA.
Regarding "fake raid" controllers, I use them in several small machines, but only as JBOD with software RAID. I haven't used Adaptec cards for many years, mostly because their SCSI controllers back in the early days were junk.
Using RAID for protecting the root/boot drives requires one bit of extra work ... make sure you install grub in the boot sector of at least two drives so you can boot from an alternate if necessary. CentOS/SL/RHEL doesn't do that for you, it only puts grub in the boot sector of the first drive in an array.
Chuck
On 03/07/11 10:43 AM, Chuck Munro wrote:
I haven't used Adaptec cards for many years, mostly because their SCSI controllers back in the early days were junk.
I blame Adaptec for the dominance of IDE. Seriously.
If Adaptec A) hadn't had the lionshare of the SCSI mindset in the PC business back in the 90s, and B) hadn't made so much overpriced buggy crap, we'd all be using SCSI today.
I blame Adaptec for the dominance of IDE. Seriously.
If Adaptec A) hadn't had the lionshare of the SCSI mindset in the PC business back in the 90s, and B) hadn't made so much overpriced buggy crap, we'd all be using SCSI today.
Yes and No. I remember playing with it back in the 90's and what drove me away from SCSI was the complexity of the standard. Yes Adaptec made it harder then it had to be but IDE, for all it's failings, was easier to use. You jumper'd one disk as master and one as slave and it pretty much just worked. SCSI on the other hand, at least in DOS/Win3/Win95/98, was a complex process involving TSR's and fiddling with jumpers on the disks & HBA. I remember my father spent six hours trying to get a simple SCSI scanner to work.
By the time RedHat 6 came out, when I made my first real foray into Linux, SCSI support was a lot better. I also took the time to sit down with a sysadmin I knew and download his knowledge about SCSI which he'd learned over the decades.
On Tue, 8 Mar 2011, Drew wrote:
I blame Adaptec for the dominance of IDE. Seriously.
If Adaptec A) hadn't had the lionshare of the SCSI mindset in the PC business back in the 90s, and B) hadn't made so much overpriced buggy crap, we'd all be using SCSI today.
Yes and No. I remember playing with it back in the 90's and what drove me away from SCSI was the complexity of the standard. Yes Adaptec made it harder then it had to be but IDE, for all it's failings, was easier to use. You jumper'd one disk as master and one as slave and it pretty much just worked. SCSI on the other hand, at least in DOS/Win3/Win95/98, was a complex process involving TSR's and fiddling with jumpers on the disks & HBA. I remember my father spent six hours trying to get a simple SCSI scanner to work.
I loved the mid-90s saying...
SCSI is like voodoo: it all depends on where you stick the pins.
Drew wrote:
I blame Adaptec for the dominance of IDE. Â Seriously.
If Adaptec A) hadn't had the lionshare of the SCSI mindset in the PC business back in the 90s, and B) hadn't made so much overpriced buggy crap, we'd all be using SCSI today.
Yes and No. I remember playing with it back in the 90's and what drove me away from SCSI was the complexity of the standard. Yes Adaptec made it harder then it had to be but IDE, for all it's failings, was easier to use. You jumper'd one disk as master and one as slave and it pretty much just worked. SCSI on the other hand, at least in DOS/Win3/Win95/98, was a complex process involving TSR's and fiddling with jumpers on the disks & HBA. I remember my father spent six hours trying to get a simple SCSI scanner to work.
<snip> Huh - odd. I know it didn't take me very long (once I'd gotten a used SIIG SCSI card from a co-worker) to get my SCSI scanner up and running under Win95 (and I still have both the card and the scanner....)
mark
My scepticism regarding SMART data continues ... the flaky drive showed no errors, and a full test and full zero-write using the WD diagnostics revealed no errors either. If the drive is bad, there's no evidence that would cause WD to issue an RMA.
I've been having a rash of drive failures recently and I have come to trust SMART.
One thing's for sure - SMART is not implemented the same on all drives or controllers. Recently one older Seagate drive showed no SMART capability in linux using the gnome-disk-utility, but I could read the SMART data from the drive in Windows with HD Tune.
It isn't infallible, but SMART is certainly one tool you can use in the diagnosis. I wouldn't ignore Reallocated Sector counts or Current Pending Sector counts, for instance.
Working for a customer this weekend, I replaced an older 60G WD drive that I knew for months to have bad sectors, but the Reallocated Sector Count was still 0. After a scan for errors with HD Tune, the Current Pending sector count showed 13, but the Reallocated Sector Count never grew.
There is still a lot for me to learn - like the relationship between SMART within the drive and the controller's support of SMART. You would think they are independent of each other, but I wonder...
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Chuck Munro -
compdoc -
Drew -
John R Pierce -
m.roth＠5-cent.us -
Paul Heinlein