Re: lvm on raid1 for a backup server or not?
Zhengquan Zhang wrote:
Dear debian community,
I will build up a backup server which has 2x1T + 1x250G drives. the size
of the one full backup will be about 400G.
My initial plan was to install debian lenny on the 250G drive. leave
2x1T drive untouched and then make software raid1 on them after the
I have a few questions that I have not figured out the answer after
1. Is it advised to install the system on the 250G drive as well as the
2x1T drive? Installing the system on 3 drives will enable the machine to
boot if the 250G drive fails. But in that case, will the machine boot
correctly using system installed on the 1T drive? and How can I directly
install the OS on 3 drives simultaneously?
you could use raid 1 with the 3 drives for the / system partition of +-
5GB and create a raid 1 /backup partition on the remaining space of the
2 TB disks.
although you then might as well not use the 250GB disk at all since it
only adds some complexity and most space on it is wasted anyway,
if you make it a system disk only, and the 250GB would fail you could
always still reach the data on the disks by mounting them in another
machine or using a live-cd or something.
it would be my idea to forget about the 250GB and just use the 2x 1TB in
a raid 1 setup
2. I have used lvm on other systems but not on raid. I wonder if it is
advisable to use lvm over raid on a backup server. The rationale of LVM
is to make resizing easier but in this situation is it advisded to use
LVM on the raid1 array and the 250G boot drive?
LVM itself works fine on top of RAID, no worries. just make sure your
raid setup is sound.
personally i always prefer to have just a small root partition and
single large partition for the data if possible and forget about adding
the extra layer.
you could use the lvm to stripe the 250 GB and the 1TB raid 1 together,
but that looses the point of data security i guess
Thanks for any pointers,