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If the md device provides the file system including /boot or is an LVM PV (physical volume) then /etc/mdadm/mdadm.conf and the initrd must be updated
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must be re-populated as shown below and the initramfs re-generated by:
update-initramfs -u
Replacing an underlying device
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| Code Block |
|---|
mdadm-startall |
Routine maintenance
checkarray
At least Debian 7 Wheezy has /etc/cron.d/mdadm which runs
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Sometimes mismatches are reported. According to https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=518834#38, that is a problem for RAID 5 but not for RAID 1. Presumably it is a problem for RAID 6 too.
Re-populating /etc/mdadm/mdadm.conf
/etc/mdadm/mdadm.conf is generated when md arrays are set up changes may require updating it by:
/usr/share/mdadm/mkconf > /etc/mdadm/mdadm.conf
Troubleshooting
initrd fails to assemble md devices
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After fixing the missing md devices as above, the VGs and LVs can be enabled by running the busybox command lvm and then using its help to find the commands to do so (cut down versions of the GNU Linux equivalents).
Messages
/etc/mdadm/mdadm.conf defines no arrays
Populate /etc/mdadm/mdadm.conf as described above.
RebuildFinished event detected on md device *, component device mismatches found: * (on raid level *)
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