Re: [tlug] Current practices for Linux partioning?

["Stephen J. Turnbull" <stephen@example.com>]

On Wed, Apr 11, 2012 at 6:16 AM, Jonathan Byrne <jonathan@example.com> wrote:
> A few weeks ago, I stumbled across this article:
>
> http://freedesktop.org/wiki/Software/systemd/separate-usr-is-broken

Yeah I just started a different thread on the same topic (with
Subject: Am I the last to know? or similar).

> Now, that just seems wrong to me; it's not the Unix Way to be unable to
> boot without /usr mounted.

As Simon says, that's a relic of partition limitations and disk size.
In practice, distros and app writers have been rather incautious about
the division between /s?bin and /usr/s?bin.  You must mount /usr on
modern systems very early unless you have a very carefully set up
server; workstations need /usr for all the fluff that all the distros
seem to think should be required.

There's nothing wrong with tradition for tradition's sake, either --
while the old ways may not be "strictly best" any more, they're
certainly good enough and have the important virtue of simplicity
(which can be analyzed into high coherence, loose coupling, and so on
-- but I digress).  But I think you should acknowledge that this is,
indeed, tradition for tradition's sake.

Personally, the things that I don't like about this are (1) backward
compatibility to my traditionally partitioned systems (on Gentoo udev
is currently in package.mask because the new update requires /usr to
be mounted and I don't know exactly what my boot sequence is so I'm
not going to chance it until I have a full day for disaster recovery
if necessary), (2) some trivial stuff like "du -x /var" as an
abbreviation for "how much is in /var except for /var/www" (and a
related issue with /var/backups, since a couple of my scripts don't
actually rotate the backups, I do that by hand when the partition
fills ;-).  Obviously, installing appropriate resource accounting
software is probably a better idea now, especially since a lot of my
resource limitation partitions are on lvm anyway!

I do like having /home and /var (and some other hierarchies with
similar usage patterns, see below) as separate partitions, as on
several occasions I've migrated to new hardware just by moving that
disk.  Of course that doesn't apply to laptops, but if it doesn't cost
anything to do it the Way You've Always Done and allows you to reduce
thinking, why not?

> As I prepare to upgrade my Envy 15 from Win 7 to Linux, what your
> thoughts around partitioning? Should I hold my nose and make a / big
> enough to contain /usr,

Yes.

> or should I Do Things The Way I've Always Done
> Them, which is this partitioning scheme:
>
> /
> /boot

+1 - you need this

> swap

+1 - no file system mounted, so strictly speaking off topic

> /tmp

If this is not a ramdisk, no.  AFAICT /tmp is used on my systems at
boot time and for my personal scratch; programs (except for my MUA,
which needs fixing in its use of temporary storage anyway) seem to use
TMPDIR=/var/tmp.  I've never seen huge files in /tmp.

> /usr

-1 - more pain than you want unless you maintain your own distro anyway

> /usr/local
> /opt

Depends on how you use them.  In my usage, /usr/local contains
personal mods, and lives with /var and /home (q.v.).  /opt is external
packages I use verbatim (including some where I follow the bleeding
edge via a VCS, but don't do any local development at all), and may as
well live with / (unless packages are badly behaved and write data,
including configuration, to the /opt hierarchy).

> /srv

Dunno.  What's this for?

> /var

Yes.  As with /home, if it's not a notebook, I prefer to have this on
a separate disk.  /var and /home can cohabit for my purposes.

> /var/spool (if it's a system that will be running an SMTP daemon; in
> this case, not)

Not obvious any more.  There are too many ways to fill /var (logs, web
site uploads, databases, etc, etc); probably it's a better idea
(assuming robust resource management software, which we presumably
have by now?) to use something more configurable than partitioning.

> /home

Yes.  In fact, I prefer /home to be on a separate disk on my
non-notebook systems.