Red Hat Bugzilla – Bug 122598
Anaconda creates suboptimal RAID5 configurations
Last modified: 2007-11-30 17:10:42 EST
From Bugzilla Helper:
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6b)
Description of problem:
Anaconda/Disk Druid creates RAID-5's with algoritm = 0
(left-assymetric.) However, the recommended algorithm for general use
is algorithm 2 (left-symmetric.)
Unfortunately, there is no easy way to recover this after system
installation, so this is a major flaw.
Version-Release number of selected component (if applicable):
FC2test3 CD ISOs
Steps to Reproduce:
1. Create a RAID-5 with Disk Druid.
2. Look at /proc/mdstat.
3. Read the md documentation.
anaconda has never set this explicitly and instead just goes with the
defaults for the raid tools/kernel. At this point, it's too late to
change for FC2 (it wouldn't get any testing at all), so targeting for FC3.
This is somewhat misleading.
Please note that raidtools are considered obsolete. mdadm defaults to
Also note this applies to RAID-6 as well as RAID-5.
Switching to madadm for FC3, changes are in CVS (which will then
follow the default of mdadm, I'm not going to change the defaults
there either since the tool should dtrt by default)