Am 23.04.2013 16:44, schrieb Tanstaafl:
> Ok, this is the last question I need to answer for myself before
> installing a final version of my new virtualized gentoo server...
> 
> I'll be using the following partition layout:
> 
> /boot (ext2), 100M
> /swap, 2G
> / (ext4), 40G
> 
> then on LVM
> 
> /tmp (ext2), 5G? <- how big?
> /var/tmp (ext2), 5G? <- how big?

If this is a production server I wouldn't use ext2. In the case of a
crash or reboot, you don't want to loose precious uptime just because of
fsck or corrupted file systems.

> /var/log (ext4) <- size? should I even have this separate?

Doesn't need to be separate but could prevent a runaway process from
filling /var just because it is spamming log entries. Could also be
achieved with quotas.

> /var (xfs), 750G
> /snapshots (xfs), 10G? <- for lvm snapshots of /var for backups
> 
> I'm not using a separate /home because there are no system users beyond
> my admin user (and the system user accounts)...
> 
> So - first, is 5G way too big for the two /tmp dirs? I have lots of
> space, but hate waste
> 

If you worry about waste consider bind-mounting both from the same
partition and install quotas to avoid one filling up the other. A bit
like poor-man's btrfs sub volumes.

Since you are using LVM you should also keep some unallocated memory,
start with smaller partitions and monitor usage. A cron job that looks
at `df` and sends a mail when a partition is more than x% full helps a lot.

> This mail server is not all that busy, and the backups only take about
> an hour, so I guesstimate that there won't be more than about 100-300MB
> of changes at the *extreme* outside of the envelope, so the 10G is most
> likely extreme overkill... but I'll know soon enough, and besides, I've
> got plenty of disk space to play with.
> 
> One question... I have some MySQL databases running on this system too,
> for my userdbs, and on the new server, SOGo (groupware)...
> 
> Is it recommended to incorporate scripts to perform dumps of the dbs, or
> is the lvm snapshot reliable enough for backing these up in their raw
> state?
> 

Restoring from lvm snapshot is like restoring after a black out or
similar crash. Having proper dumps is always a good idea.

> Thanks as always for comments/suggestions/criticisms...
> 

Hope this helps,
Florian Philipp