[Beowulf] Re: RAID for home beowulf

[Tomislav Maric]

Hi Jörg,

thanks for the info. I'm converging to the solution regarding RAID now.
Thank you a lot for the link I'll be needing it. :)

Well, I don't need too much scratch space, the important part of the
disk is the /home with the results. What file system should I use for
it, ext3?

Best regards,
Tomislav

Jörg Saßmannshausen wrote:
> Hi Tomislav 
> 
> I agree with what Skylar wrote. However, ask yourself what are you going to do 
> with the cluster?
> For example, I am doing quite a lot of molecular modelling, which requires 
> plenty of RAM and also scratch space. 
> So for the machines at the old University, I set up /boot and / as RAID1. Why? 
> Failover is the answere. In case one disc dies, I have degraded, but working 
> machine and the next possible time I can sort out the broken hdd. Actually, I 
> had to do that a few times as somehow the IDE hdd seem to be a bit dogdy and 
> broke quickly. Fortunately, within one day everything was back in working 
> order (I swapped both discs in that occassion, so I had to mirror twice). 
> There is a HowTo setup a failover boot as well.
> ( http://www200.pair.com/mecham/raid/raid1.html )
> 
> Also, if what you are doing needs plenty of scratch space, I would recommend a 
> RAID0 and xfs. Best to do that as a hardware raid as it is faster than a 
> software raid.
> 
> I hope that helps a bit.
> 
> All the best
> 
> Jörg
> 
> 
> Am Samstag 03 Oktober 2009 schrieb beowulf-request at beowulf.org:
>> Message: 2
>> Date: Sat, 03 Oct 2009 19:41:28 +0200
>> From: Tomislav Maric <tomislav.maric at gmx.com>
>> Subject: [Beowulf] RAID for home beowulf
>> To: beowulf at beowulf.org
>> Message-ID: <4AC78CC8.5060500 at gmx.com>
>> Content-Type: text/plain; charset=ISO-8859-1
>>
>> Hi everyone,
>>
>> I've finally gathered all the hardware I need for my home beowulf. I'm
>> thinking of setting up RAID 5 for the /home partition (that's where my
>> simulation data will be and RAID 1 for the system / partitions without
>> the /boot.
>>
>> 1) Does this sound reasonable?
>> 2) I want to put the /home at the beginning of the disks go get faster
>> write/seek speeds, if the partitions are the same, software RAID doesn't
>> care where they are?
>> 3) I'll leave the /boot partition on one of the 3 disks and it will NOT
>> be included in the RAID array, is this ok?
>> 4) I've read about setting up parallel swaping via priority given to
>> swap partitions in fstab, but also how it would be ok to create RAID 1
>> array of swap partitions for the HA of the cluster. What should I choose?
>>
>> I've gone through all the software raid how-tos, FAQs and similar, but
>> they are not quite new (date at least 3 years) and there's no reference
>> to clusters. Any pointers regarding this?
>>
>> Thank you in advance,
>> Tomislav
>>
>> I'm starting with this:
>>
>> 3 x Asus P5Q-VM motherboards
>> 2 x Intel Quad Core Q8200 2.33GHz (2 nodes with 4 cores)
>> 1 x Intel Core 2 Duo E6300 2.6GHz (master node)
>> 3 x Seagate Barracuda 320GB SATA 2 HDDs
>>
>> gigabyte Eth switch with 8 ports .... etc ...
>>
>> Best regards,
>> Tomislav