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<pre wrap=""><b>I M P O R T A N T ! ! !
Note: copied from Scientific Linux list</b> Konstantin Olchanski <a class="moz-txt-link-rfc2396E" href="mailto:olchansk@triumf.ca"><olchansk@triumf.ca></a>
"======================================
FYI, as a regression from SL6.0 and SL6.1, SL6.2 does not boot from degraded RAID1 devices.
If your "/" is on a RAID1 mirrored across 2 disks and <b>1 of the 2 disks dies,</b> <b>your system will
not boot</b> because dracut does not activate the required md devices.
This is a very serious problem because RAID1 (mirroring) of "/" and "swap" is a popular
solution for protecting against single-disk failures. The present bug defeats this protection
and makes the situation worse because failure of either of the 2 disks makes your system
unbootable.
It is astonishing that this problem was not caught by anybody's QA, did not receive
wide publicity <b class="moz-txt-star"><span class="moz-txt-tag">*</span>and<span class="moz-txt-tag">*</span></b> the solution was not pushed into the current release of SL.
Bug report against dracut was filed in January:
<a class="moz-txt-link-freetext" href="https://bugzilla.redhat.com/show_bug.cgi?id=772926">https://bugzilla.redhat.com/show_bug.cgi?id=772926</a>
marked as duplicate of secret bug:
<a class="moz-txt-link-freetext" href="https://bugzilla.redhat.com/show_bug.cgi?id=761584">https://bugzilla.redhat.com/show_bug.cgi?id=761584</a>
solution made available in July for (the best I can tell) the 6.3 release:
<a class="moz-txt-link-freetext" href="http://rhn.redhat.com/errata/RHBA-2012-0839.html">http://rhn.redhat.com/errata/RHBA-2012-0839.html</a> (dracut-004-283.el6.src.rpm)
<a class="moz-txt-link-freetext" href="http://rhn.redhat.com/errata/RHBA-2012-1078.html">http://rhn.redhat.com/errata/RHBA-2012-1078.html</a> (dracut-004-284.el6_3.src.rpm)
These RPMs are available in SL6 .../6rolling/x86_64/updates/fastbugs/
I confirm that dracut-004-284.el6_3 can boot SL6.2 from degraded "/" (one disk missing).
Note that applying the fix on affected systems is not trivial:
1) rpm -vh --upgrade dracut-004-284.el6_3.noarch.rpm dracut-kernel-004-284.el6_3.noarch.rpm
2) bad dracut is still present inside the /boot/initramfs files, your system is still broken
3) dracut -v -f ### this rebuilds the initramfs for the ***presently running*** kernel, not necessarily the one used for the next reboot
4) find /boot -name 'initramfs*.img' -print -exec lsinitrd {} \; | grep dracut-0 ### report dracut version inside all /boot/initramfs files
5) dracut -v -f /boot/initramfs-2.6.32-279.1.1.el6.x86_64.img 2.6.32-279.1.1.el6.x86_64 ### rebuild initramfs for the latest update kernel
"=======================================
Is fixed is SL6-3
Looks like CentOS with its 6,3 version is OK
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