[CentOS] Clustering

Fri Feb 5 19:21:33 UTC 2010
Les Mikesell <lesmikesell at gmail.com>

On 2/5/2010 10:04 AM, nate wrote:
>
>> Have you investigated any of the mostly-software alternatives for this like
>> openfiler, nexentastor, etc., or rolling your own iscsi server out of
>> opensolaris or centos?
>
> I have and it depends on your needs. I ran Openfiler a couple years
> ago with ESX and it worked ok. The main issue there was stability. I
> landed on a decent configuration that worked fine as long as you
> didn't touch it(kernel updates often caused kernel panics on the
> hardware which was an older HP DL580). And when Openfiler finally came
> out with their newer "major" version the only upgrade path was to
> completely re-install the OS(maybe that's changed now I don't know).

Somewhere along the line they switch from a CentOS base to rpath for 
better package management, but I haven't followed them since.

[...]
> Another advantage to a proper enterprise-type solution is support,
> mainly for firmware updates. My main array at work for example is
> using Seagate enterprise SATA drives. The vendor has updated the
> firmware on them twice in the past six months. So not only was the
> process made easy since it was automatic, but since it's their
> product they work closely with the manufacturer and are kept in the
> loop when important updates/fixes come out and have access to them,
> last I checked it was a very rare case to be able to get HDD firmware
> updates from the manufacturer's web sites.

I had an equally frustrating experience with a Dell rebranded NetApp 
several years back.  The unit shipped with a bad moherboard FC 
controller which was a known problem and they also included an add-on 
card.  But, the guy who set it up called support where he was told that 
the problem had been fixed by this serial number and he should connect 
to the motherboard port.  The symptom was that once or twice a year it 
would see something wrong with a drive, kick it out and rebuild on a hot 
spare.  Eventually it lost several disks at once and lost the data. 
After I dug up the history I switched controllers and reinstalled 
everything from scratch and it worked after that, but by then nobody 
trusted it and it was only used for backups.   So, I no longer believe 
that paying a lot for a device that is supposed to have a good 
reputation is a sure thing - or that having a support phone number is 
going to make things better.  Everyone has different war stories, I guess...

> A co-worker of mine had to update the firmware on some other Seagate
> disks(SCSI) in 2008 on about 50 servers due to a performance issue
> with our application

Oh yeah - the drives in this device needed that too - but it wasn't that 
bad to do on one device with the NetApp software.

-- 
   Les Mikesell
    lesmikesell at gmail.com