Re: [gentoo-user] Advice/best practices for a new Gentoo installation

[Alex Schuster <wonko@wonkology.org>]

Paul Hartman writes:

> - utilizing device labels and/or volume labels instead of hoping
> /dev/sda stays /dev/sda always

Good idea. Or use LVM.

> - better partitioning scheme than my current root, boot, home (need
> portage on its own, maybe /var as well?)

I like to have many partitions. When my /usr/portage/distfiles or /tmp 
gets full, I do not want this to affect my system.

> - some kind of small linux emergency/recovery partition? equivalent to
> a liveCD maybe.

Maybe, but a liveCD is also fine and can be used elsewhere, too.

> - best filesystem for portage? something compressed or with small
> cluster size maybe.

I think reiserfs with the notail option is recommended.

> - omit/reduce number of reserved-for-root blocks on partitions where
> it's not necessary.

I reduce it for large partitions, but do not set it to 0 in order to 
prevent fragmentation.

> - I have never used LVM and don't really know about it. Should I use
> it? will it make life easier someday? or more difficult?

A little more difficult in the first place, until you get used to it. But 
if you need to change things later, it makes this much easier. /var is too 
small? Well, enter lvresize -L +1G /dev/myvg/var && resize2fs 
/dev/myvg/var and you have 1G more of space after half a minute. No need 
to take the system down, boot a rescue system and use parted.

Short how-to:
- create some partitions you will use for LVM (/dev/sda[56789])
- make them physical volumes: pvcreate /dev/sda[56789]
- make them a volume group:   vgcreate myvg /dev/sda[56789]
- create logical volumes:     lvcreate -L 5G -n usr myvg (/usr partition)
- create file system:         mke2fs -j -L usr /dev/myvg/usr

> - Is RAID5 still a good balance for disk cost vs usable space vs data
> safety? I can't/don't want to pay for full mirroring of all disks.

Probably, if you need RAID. But I'd say RAID is not a real backup, so you 
would need even more disks space for that. I prefer to use a 2nd disk for 
backups I make frequently with rdiff-backup. They have the same structure 
as the original, only that each partition has an additional 'rdiff-backup-
data' directory that stores the data of older snapshots.
Some months ago my main drive started having errors, so I took it out, 
booted with a CD, renamed the volume group of the backup disk to that of 
the original one ("vgrename backup system"), and that was all. Using RAID 
would have been even easier, but does not help when I accidentally remove 
a file, or want a file as it was a whiel ago.
Keeping the older snapshots needs some extra space, but this is 
compensated by not having to backup everything including 
/usr/portage/distfiles, /var/tmp/portage etc.

	Wonko