[Beowulf] RAID for home beowulf

[John Hearns]

2009/10/5 Mark Hahn <hahn at mcmaster.ca>:
>> the other nodes are to be diskless.. I have separated these partitions:
>>  /swap /boot /  /var and /home. Is this ok?
>
> I don't believe there is much value in separating partitions like this.
> for instance, a swap partition has no advantage over a swap file,
> and the latter is generally more convenient.  separating /boot is largely a
> vestige of quite old bioses which could not do 48b LBA addressing (ie, deal
> with big disks.)  separating /, /var and /home
> is largely a matter of taste:

I agree with what Mark says.
Many separate partitions were necessary in the 'old days' when disks
were small - so the partitioning reflects in fact using separate disks
on a SCSI chain. I still vote for a separate /boot partition though -
much more in my comfort zone.
I was going to say that having a single /boot means that you can have
a system with several distros or releases  and boot into whichever
root filesystem you choose. But I'm talking nonsense - I had an
openSUSE dekstop with half this disk empty the other week. I put SLED
10 on there as well for tests - the installer recognised first time
that there was an existing install and put its parameters in the grub
menu!

 A common layout is to have a separate /home. Then some smart-assed
user filling his/her home filesystem can't drag the rest of the system
down.

For CFD applications you definitely need some larger area of disk
which is fast storage. I would definitely NOT put this on the system
disk, no matter how big it is, for reasons that Mark says. You either
want NFS on a pretty well performing server, with a fat network pipe
and striped disks, or a parallel filesystem.