Neil,
Please consider this patch that once was discussed and I think agreed with in general direction. It was sent a while ago
but somehow did not merged into your devel3-2. This patch enables hot-plug of so called bare devices (as understand by domain policies rules in mdadm.conf).
Without this patch we do NOT serve hot-plug of bare devices at all.
Thanks,
Marcin Labun
Subject was: FW: Autorebuild, new dynamic udev rules for hot-plugs
>>From c0aecd4dd96691e8bfa6f2dc187261ec8bb2c5a2 Mon Sep 17 00:00:00 2001
From: Przemyslaw Czarnowski <przemyslaw.hawrylewicz.czarnowski@intel.com>
Date: Thu, 23 Dec 2010 16:35:01 +0100
Subject: [PATCH] Dynamic hot-plug udev rules for policies
Cc: linux-raid@vger.kernel.org, Williams, Dan J <dan.j.williams@intel.com>, Ciechanowski, Ed <ed.ciechanowski@intel.com>
When introducing policies, new hot-plug rules were added to support
bare disks. Mdadm was started for each hot plugged block device
to determine if it could be used as spare or as a replacement member for
degraded array.
This patch introduces limitation of range of devices that are handled
by mdadm.
It limits them to the ones specified in domains associated with
the actions: spare-same-port, spare and spare-force.
In order to enable hot-plug for bare disks one must update udev rules
with command
mdadm --activate-domains[=filename]
Above command writes udev rule configuration to stdout. If 'filename'
is given output is written to the file provided as parameter. It is up
to system administrator what should be done later. To make such rule
permanent (i.e. remain after reboot) rule should be writen to
/lib/udev/rules.d directory. Other cases will just need to write it to
/dev/.udev/rules.d directory where temporary rules lies. One should be
aware of the meaning of names/priorities of the udev rules.
After mdadm.conf is changed one is obliged to re-run
"mdadm --activate-domains" command in order to bring the system
configuration up to date.
All hot-plugged disks containing metadata are still handled by existing
rules.
Signed-off-by: Przemyslaw Czarnowski <przemyslaw.hawrylewicz.czarnowski@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Though not having the proper backup file can cause data corruption, it
is not enough to justify not being able to start the array at all.
So allow "--invalid-backup" to be specified which says "just continue
even if a backup cannot be restored".
Signed-off-by: NeilBrown <neilb@suse.de>
In several cases, two different long options map to the same short
option. So e.g. you could give '--brief' and it would be interpreted
as '--bitmap'. That isn't really good.
So for every shared short option, define an option number and return
that for the long option instead. Then always check for both the
short and long options.
Also give some bugs like " mode == 'G'" which should be '== GROW'.
Signed-off-by: NeilBrown <neilb@suse.de>
In order to support reshape and atomic removal of spares from containers
we need to prevent mdmon from activating spares. In the reshape case we
additionally need to freeze sync_action while the reshape transaction is
initiated with the kernel and recorded in the metadata.
When reshaping a raid0 array we need to freeze the array *before* it is
transitioned to a redundant raid level. Since sync_action does not exist
at this point we extend the '-' prefix of a subarray string to flag
mdmon not to activate spares.
Mdadm needs to be reasonably certain that the version of mdmon in the
system honors this 'freeze' indication. If mdmon is not already active
then we assume the version that gets started is the same as the mdadm
version. Otherwise, we check the version of mdmon as returned by the
extended ping_monitor() operation. This is to catch cases where mdadm
is upgraded in the filesystem, but mdmon started in the initramfs is
from a previous release.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
--no-sharing option disables moving spares between arrays/containers.
Without the option spares are moved if needed according to config rules.
We only allow one process moving spares started with --scan option.
If there is such process running and another instance of Monitor
is starting without --scan, then we issue a warning but allow it
to continue.
Signed-off-by: Anna Czarnowska <anna.czarnowska@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
<path-id> allows to identify the port to which given device is plugged
in. In case of hot-removal, udev can pass this information for future
use (eg. write this name as 'cookie' allowing to detect the fact of
reinserting device to the same port).
--path <path-id> parameter has been added to device removal handle
(and char *path has been added to IncrementalRemove() to pass this
value) in order to pass path-id to this handler.
Signed-off-by: Przemyslaw Czarnowski <przemyslaw.hawrylewicz.czarnowski@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
This can be used for hot-unplug. When a device has been remove,
udev can call
mdadm --incremental --fail sda
and mdadm will find the array holding sda and remove sda from
the array.
Based on code from Doug Ledford <dledford@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
In some places it is referred to as "--rebuild", and while
that works due to getopt allowing prefixes, it could appear
confusing (rebuild means other things too) and being explicit
is some safeguard if we want to add e.g. --rebuild-foo later.
Reported-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Allow the name of the array stored in the metadata to be updated. In
some cases the metadata format may not be able to support this rename
without modifying the UUID. In these cases the request will be blocked.
Otherwise we allow the rename to take place, even for active arrays.
This assumes that the user understands the difference between the kernel
node name, the device node symlink name, and the metadata specific name.
Anticipating further need to modify subarrays in-place, introduce the
->update_subarray() superswitch method. A future potential use
case is setting storage pool (spare-group) identifiers.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Support for deleting a subarray out of a container. When all subarrays
are deleted the component devices are converted back into spares, a
--zero-superblock is still needed to kill the remaining metadata at this
point. This operation is blocked when the subarray is active and may
also be blocked by the metadata handler when deleting the subarray might
change the uuid of other active subarrays. For example, with imsm,
deleting subarray 'n' may change the uuid of subarrays with indexes > n.
Deleting a subarray needs to be a container wide event to ensure
disks that record the modified subarray list perceive other disks that
did not receive this change as out of date.
Notes:
The st->subarray parsing in super-intel.c and super-ddf.c is updated to
be more strict now that we are reading user supplied subarray values.
Offline container modification shares actions that mdmon typically
handles so promote is_container_member() and version_to_superswitch()
(formerly find_metadata_methods()) to generic utility functions for the
cases where mdadm performs the operation.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
ie. the percent increments after which RebuildNN event is generated
This is particulary useful when using --program option, rather than
(only) syslog for alerts.
Signed-off-by: Zdenek Behan <rain@matfyz.cz>
Signed-off-by: NeilBrown <neilb@suse.de>
With 2.6.30 it is possible to tell the md driver to clip an array to a
size smaller than the real size of the array. This option gives
access to that feature. The size change does not persist
across restarts.
Signed-off-by: NeilBrown <neilb@suse.de>
DDF raid6 layouts are subtly different from the standard 'md' layouts.
From 2.6.30 the kernel knows about these.
Teach mdadm about them, and also allow 'ddf' to set an appropriate default.
Signed-off-by: NeilBrown <neilb@suse.de>
Metadata formats like imsm work in concert with platform firmware and
hardware, so provide a way for mdadm to display this info to the user.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
For use in distro shutdown scripts with a RAID root file system.
Returns immediately if the array is 'readonly', or not an externally
managed array. It is up to the distro's scripts to make sure no new
writes hit the device after this returns 'true'.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>