[SOLVED] new to ubuntu- random RAID mdadm daemon checks?

[alecm3]

I'm gonna get hammered for this but software RAID has no business on a "production" server. You found one of the reasons. It takes resources.

Do you even need RAID? Remember, it's no substitute for good backups. I am just curious, if you are new to Ubuntu, what made you decide you HAD to have RAID on your server? I'm just really curious where this is all coming from.

Also, when you say "production", what are we talking here, 1 web site? 30? 300?

-Tim

You have never worked in professional IT dealing with large deployments.

Running one website with multiple database servers, bandwidth 100Mbps and knowing what we are doing. Have been using software RAID for 5 years with success, others with even bigger setups (of the order of 100 DB servers) are using it as well. In fact, we did extensive benchmarking, and software RAID is much more stable and in many cases faster than embedded RAID (like LSI controllers).
I would reserve your posting style for Digg, not for Linux forums.



Here is the answer to my own question:

This problem is listed as Ubuntu bug:

https://bugs.launchpad.net/ubuntu/+s...ux/+bug/212684

There is a cron script
/etc/cron.d/mdadm
which runs /usr/share/mdadm/checkarray on the first Sunday of each month (which happened yesterday).

root@db2:/etc/cron.d# more mdadm
#
# cron.d/mdadm -- schedules periodic redundancy checks of MD devices
#
# Copyright © martin f. krafft <madduck@madduck.net>
# distributed under the terms of the Artistic Licence 2.0
#
# $Id$
#

# By default, run at 01:06 on every Sunday, but do nothing unless the day of
# the month is less than or equal to 7. Thus, only run on the first Sunday of
# each month. crontab(5) sucks, unfortunately, in this regard; therefore this
# hack (see #380425).
6 1 * * 0 root [ -x /usr/share/mdadm/checkarray ] && [ $(date +\%d) -le 7 ] && /usr/share/mdadm/checkarray --cron --a
ll --quiet

Apparently, this cron killed the systems for quite a lot of people:
http://ubuntuforums.org/showthread.php?t=748418 etc