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D'oh, forgot a title.

Apparently brian wants me to write the article just on List::Part.  Which is alright, though I'm not sure there's enough material for a full article.

The other thing I did yesterday was set up RAID on the server.  For those who haven't had it beaten into their skulls yet, RAID is a way of combining multiple disks into a whole that's faster and more reliable than the sum of its parts.  I'm using RAID-5, which uses "striping" (data is alternated between disks) and "parity" (backup data is stored in such a way that a disk can go bad without losing any data).

To review, Navi has these drives:
hda (60GB)hde (10GB)hdg (10GB)
/boot (32MB), root (1GB), swap (1GB?)
/usr (13GB)
/var (13GB)
/home (13GB)
/tmp (2.5GB)
Empty (5GB)
md0 part one (5GB)md0 part two (5GB)md0 part three (5GB)
md1 part one (5GB)md1 part two (5GB)md1 part three (5GB)
A third of the space on md0 and md1 are used by parity data, so each of them is about 10GB.

Each of md0 and md1 contains one big folder that needs to be kept safe, and one smaller one that does as well.  md0 contains /var/www (all web files, including Filespace) and /var/svn (Subversion version-control files).  md1 contains /var/lib/mysql (MySQL databases) and /var/qmail/queue (the Qmail incoming mail queue, which can't really be backed up because it changes constantly).  Because there are two folders in each md (multi-disk) volume, I can't just mount them directly into the folders; instead, I do this:
/dev/md0        /mnt/md0          ext3  defaults  1 2
/dev/md1        /mnt/md1          ext3  noatime   1 2

/mnt/md0/www    /var/www          none  bind      0 0
/mnt/md0/svn    /var/svn          none  bind      0 0
/mnt/md1/mysql  /var/lib/mysql    none  bind      0 0
/mnt/md1/queue  /var/qmail/queue  none  bind      0 0
This bit of chicanery in my /etc/fstab says "mount md0 and md1 onto /mnt/md0 and /mnt/md1, then bind-mount their subdirectories into place".  Which is interesting, to say the least, but it works quite well.