Re: [SLUG] RAID and LVM

[Paul De Audney <pdeaudney@xxxxxxxxx>]

Hi,

On Thu, Feb 18, 2010 at 3:18 PM, Nigel Allen <dna@xxxxxxxxxxx> wrote:

> I want to set up a pair of 1 TB drives on an HP DL145 G3 and I'm looking for
> suggestions as to the best way to partition them.
>
> Would I be best using software RAID and LVM? Given that it's a fairly busy
> machine (mail server for 40+ users) I'd like to achieve:
>
> 1) Speed

How much speed do you really need for a email server?
For 40-100 users 2x SATA drives in software raid 1 should be sufficient.

> 2) Reliability

Sure software raid 1 will give you that. Make sure you install grub on
both drives so you can boot off either in case one dies.
Also make sure you monitor for failures.

> 3) Ease of maintenance.

Document the setup. And keep the docs current.

> Anyone care to take a punt at a layout?

This really depends on your requirement for how much email you want to
store on the system, duration of logs etc.
Will the system be doing anything else? If so the layout might change.

I would personally use something along the lines of the following.

/boot (md0 100mb)

Create another raid 1 array md1 & fully allocate this to a PV. I
usually call the PV the hostname of the machine.
So if I need to access the disk/s from another system I know which
system the disk is from.

/ - LV called root 3-4GB
/var/spool/mail - LV called mailspool 1-5 GB (I am assuming I would be
storing mail elsewhere such as /home/user/Maildir)
/var/log - LV called logs, 5 GB to start with. I'd also have mail logs
compressed and rotated daily. Archive as long as you need too.
/home - LV called home, 50GB to what ever you deem required for user
email storage needs. I'd have users storing mail in their home
directories so they can use IMAP and leave mail on the server.

If I was doing anything with a database, I would have a dedicated LV
for /var/lib/mysql or /var/lib/pgsql. This would allow me to snapshot
those volumes for backups etc.

Hope this gives you some ideas.

--
Paul