[colug-432] How to Make /var Persist

[Rob Stampfli]

On Thu, Feb 23, 2012 at 09:03:18PM -0500, Scott Merrill wrote:
> On Thu, Feb 23, 2012 at 8:51 PM,  <jep200404 at columbus.rr.com> wrote:
> > On Thu, 23 Feb 2012 20:40:07 -0500, Rob Funk <rfunk at funknet.net> wrote:
> >> That would be Bad. Everything in the system assumes that /var persists
> >> across reboots ...
> >
> > Nuts. How about saving a copy (such as a tarball) of /var to flash
> > when shutting down, and restoring when booting? Definitely icky.
> 
> Terribly, terribly icky. Not to mention fragile.
> 
> > How would you solve Rob's Sheevaplug problem?
> 
> I have a Pogoplug booting off a USB flash drive. I disabled all
> unnecessary services to minimize writes. For this device, I consider
> syslog to be an unnecessary service. :)

Actually, perhaps the most significant change you can make to minimize
*nix file system writes is to mount all flash file systems with either
the "relatime" or "noatime" option.  (To a lesser extent, using EXT2
instead of EXT3 or EXT4 results in fewer writes, too.)

Understand, I solved my SheevaPlug problem by replacing the defective
SD-card.  The question I posed earlier pertained more to whether solid
state disks are as reliable as traditional hard drives with respect to
detecting and reporting errors and with respect to early-failure SMART
HD technology.

Rob