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Re: NFS recommendation



Udi Finkelstein writes:

 > 2. Is it possible to configure all 3 disks as one single ext2 partition, on a
 > standard kernel? I know there are patches for that, but I'd rather install
 > something simple that works out of the box.

What you're looking for is RAID, and all the software is already in
the kernel, so you don't need external patches. That's 100% true for
2.2 kernels. As to 2.0 kernels, AFAIR they only had *some* of the
modes, namely linear appending and striping, which is what you need
anyway. But that needs to be checked again.

The trouble is -- it's hard to boot from such a partiton. You have to
make an initrd image, and that's more mess than just "make bzImage
install". The alternative is to leave the root partition as a normal
partition and mount all the important stuff (e.g. /usr & /var) as RAID 
partitions. This should be much easier.

A piece of advice: it's a good idea to have the partitions you RAID
together the same size. So my suggested disk division should be
something like this:

on each disk, the first 128 MB are left untouched; on the first disk
that will be the root partition, and on the other two disks these will 
be swap partitions (make sure you hand-assign them the same priority
in /etc/fstab by setting pri=1 in the options field, so that they are
striped and thus swap is twice as fast);

the second partitions on all disks are striped together in a RAID0
setup to be mounted under /usr;

the third partitions on all disks are striped together in a RAID0
setup to be mounted under /var.

When you create the RAID0 setups and set the striping parameters, make 
sure the stripe size is big (e.g. 128k), it is best for big files.


-- 
Alex Shnitman                            | http://www.debian.org
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