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Giving volume type information about being 'metadata' type of volume
has higher priority then i.e. 'mirror' or 'thin' flag - for those
type we have 'target attr' (7th. field).
Last commit made dump filter only partially composable.
Add remaining functionality and also support composable wipe,
which is needed, when i.e. vgscan needs to remove cache.
(in release fix)
Add a generic dump operation to filters and make the composite filter call
through to its components. Previously, when global filter was set, the code
would treat the toplevel composite filter's private area as if it belonged a
persistent filter, trying to write nonsense into a non-sensical file.
Also deal with NULL cmd->filter gracefully.
The global filter in system's lvm.conf may conflict with the custom filter we
set up in vgimportclone (they can easily fail to intersect). Since we explicitly
avoid talking to lvmetad in vgimportclone, it is safe and reasonable to do so.
There is no point in creation of 2chunks snapshot,
since the snapshot is invalidated immeditelly with the first write
as there is no free chunk for COW blocks
(2 chunks are used by the snap header and the 1st. metadata chunk).
Enhance error message about the lowest usable size.
Instead of seeing wierd overflows inside the lvm code,
giving false error messages, kill the user experiment in the begining.
Who needs to use more then 16EiB with lvm2 and 64bit anyway...
Avoid hitting memory corruption (double free) in code path,
where PV FID has been already destroyed and the released pointer
was left in PV structure and could have been tried to be released
from there 2nd. time with final context destruction.
Check for mounted fs also for vgchange command, not just lvchange.
NOTE: Code is using lv_info() just like lvs_in_vg_opened().
It should be probably converted into lv_is_active_locally().
There are places where 'lv_is_active' was being used where it was
more correct to use 'lv_is_active_locally'. For example, when checking
for the existance of a kernel instance before asking for its status.
Most of the time these would work correctly. (RAID is only allowed on
non-clustered VGs at the moment, which means that 'lv_is_active' and
'lv_is_active_locally' would give the same result.) However, it is
more correct to use the proper variant and it helps with future
scenarios where targets might be allowed exclusively (or clustered) in
a cluster VG.
Accept --yes on all commands, even ones that don't today have prompts,
so that test scripts that don't care about interactive prompts no
longer need to deal with them.
But continue to mention --yes only in the command prototypes that
actually use it.
This fixes a long standing regression since LVM2 2.02.74 (commit 4efb1d9c,
"Update heuristic used for default and detected data alignment.")
The default PE alignment could be used (via MAX()) even if it was
determined that the device's MD stripe width, or minimal_io_size or
optimal_io_size were not factors of the default PE alignment (either 64K
or the newer default of 1MB, etc). This bug would manifest if the
default PE alignment was larger than the overriding hint that the
device provided (e.g. default of 1MB vs optimal_io_size of 768K).
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
If the dm_realloc would fail, the already allocate _maps_buffer
memory would have been lost (overwritten with NULL).
Fix this by using temporary line buffer.
Also add a minor cleanup to set end of buffer to '\0',
only when we really know the file size fits the preallocated buffer.
Setting the cmd->default_settings.udev_fallback also requires DM
driver version check. However, this caused useless mapper/control
access with ioctl if not needed actually. For example if we're not
using activation code, we don't need to know the udev_fallback as
there's no node and symlink processing.
For example, this premature mapper/control access caused problems
when using lvm2app even when no activation happens - there are
situations in which we don't need to use mapper/control, but still
need some of the lvm2app functionality. This is also the case for
lvm2-activation systemd generator which just needs to look at the
lvm2 configuration, but it shouldn't touch mapper/control.
Add new lvs segment field 'Monitor' showing 3 states:
"monitored" - LV is monitored by dmeventd.
"not monitored" - LV is currently not being monitored by dmeventd
"" (empty) - LV does not support monitoring, or dmeventd support
is not compiled in.
Support for exclusive activation of snapshots revealed some problems.
When snapshot is created, COW LV is activated first (for clearing) and
then it's transformed into snapshot's COW LV, but it has left the lock
for such LV active in cluster and this lock could not have been removed
from dlm, unless snapshot has been removed within same dlm session.
If the user tried to remove snapshot after rebooting node, the lock was
missing, and COW LV could not have been detached.
Patch modifes the approach in this way:
Always deactivate COW LV for clustered vg after clearing (so it's
activated again via imlicit snapshot activation rule when snapshot is activated).
When snapshot is removed, activate COW LV as independend LV, so the lock
will exist for such LV, but only when the snapshot is active.
Also add test case for testing snapshot removal after cluster reboot.
Patch fixes hidden problem with lvm metadata caching.
When the pretest was made, only the commited data have been cached back
since the call lv_info_by_lvid() triggers mda read operation.
However call of lv_suspend_if_active() also reads precommited metadata.
The problem is visible in this sequence of calls:
vg_write(), suspend_lv(), vg_commit(), resume_lv()
which may end with leaving outdated mda in lvm cache, since vg_write()
drops cached metadata and vg_commit() only transforms precommited
to commited metadata, but in the case of pretesting we have
no precommited mda available so the cache will continue to use
old metadata. This happens, when suspend LV is inactive.
Merging multiple config files together needs to know newest (highest)
timestamp of merged files. Persistent cache file is being used
only in case, the config file is older then .cache file.
Assign fid as the last step before returning VG.
Make the format reader for 'lvm1' and 'pool' equal to 'lvm2' format reader.
It has caused memory corruption to lvmetad as it later calls
destroy_instance() to allocated fid. This patch should fix problems
with crashing test lvmetad-lvm1.sh.
'lvchange' is used to alter a RAID 1 logical volume's write-mostly and
write-behind characteristics. The '--writemostly' parameter takes a
PV as an argument with an optional trailing character to specify whether
to set ('y'), unset ('n'), or toggle ('t') the value. If no trailing
character is given, it will set the flag.
Synopsis:
lvchange [--writemostly <PV>:{t|y|n}] [--writebehind <count>] vg/lv
Example:
lvchange --writemostly /dev/sdb1:y --writebehind 512 vg/raid1_lv
The last character in the 'lv_attr' field is used to show whether a device
has the WriteMostly flag set. It is signified with a 'w'. If the device
has failed, the 'p'artial flag has priority.
Example ("nosync" raid1 with mismatch_cnt and writemostly):
[~]# lvs -a --segment vg
LV VG Attr #Str Type SSize
raid1 vg Rwi---r-m 2 raid1 500.00m
[raid1_rimage_0] vg Iwi---r-- 1 linear 500.00m
[raid1_rimage_1] vg Iwi---r-w 1 linear 500.00m
[raid1_rmeta_0] vg ewi---r-- 1 linear 4.00m
[raid1_rmeta_1] vg ewi---r-- 1 linear 4.00m
Example (raid1 with mismatch_cnt, writemostly - but failed drive):
[~]# lvs -a --segment vg
LV VG Attr #Str Type SSize
raid1 vg rwi---r-p 2 raid1 500.00m
[raid1_rimage_0] vg Iwi---r-- 1 linear 500.00m
[raid1_rimage_1] vg Iwi---r-p 1 linear 500.00m
[raid1_rmeta_0] vg ewi---r-- 1 linear 4.00m
[raid1_rmeta_1] vg ewi---r-p 1 linear 4.00m
A new reportable field has been added for writebehind as well. If
write-behind has not been set or the LV is not RAID1, the field will
be blank.
Example (writebehind is set):
[~]# lvs -a -o name,attr,writebehind vg
LV Attr WBehind
lv rwi-a-r-- 512
[lv_rimage_0] iwi-aor-w
[lv_rimage_1] iwi-aor--
[lv_rmeta_0] ewi-aor--
[lv_rmeta_1] ewi-aor--
Example (writebehind is not set):
[~]# lvs -a -o name,attr,writebehind vg
LV Attr WBehind
lv rwi-a-r--
[lv_rimage_0] iwi-aor-w
[lv_rimage_1] iwi-aor--
[lv_rmeta_0] ewi-aor--
[lv_rmeta_1] ewi-aor--
Move common code for changing activation state from
vgchange and lvchange to one function.
Fix the order of checks - so we always implicitelly
activate snapshots and thin volumes in exclusive mode,
and we do not allow local deactivation for them.
New options to 'lvchange' allow users to scrub their RAID LVs.
Synopsis:
lvchange --syncaction {check|repair} vg/raid_lv
RAID scrubbing is the process of reading all the data and parity blocks in
an array and checking to see whether they are coherent. 'lvchange' can
now initaite the two scrubbing operations: "check" and "repair". "check"
will go over the array and recored the number of discrepancies but not
repair them. "repair" will correct the discrepancies as it finds them.
'lvchange --syncaction repair vg/raid_lv' is not to be confused with
'lvconvert --repair vg/raid_lv'. The former initiates a background
synchronization operation on the array, while the latter is designed to
repair/replace failed devices in a mirror or RAID logical volume.
Additional reporting has been added for 'lvs' to support the new
operations. Two new printable fields (which are not printed by
default) have been added: "syncaction" and "mismatches". These
can be accessed using the '-o' option to 'lvs', like:
lvs -o +syncaction,mismatches vg/lv
"syncaction" will print the current synchronization operation that the
RAID volume is performing. It can be one of the following:
- idle: All sync operations complete (doing nothing)
- resync: Initializing an array or recovering after a machine failure
- recover: Replacing a device in the array
- check: Looking for array inconsistencies
- repair: Looking for and repairing inconsistencies
The "mismatches" field with print the number of descrepancies found during
a check or repair operation.
The 'Cpy%Sync' field already available to 'lvs' will print the progress
of any of the above syncactions, including check and repair.
Finally, the lv_attr field has changed to accomadate the scrubbing operations
as well. The role of the 'p'artial character in the lv_attr report field
as expanded. "Partial" is really an indicator for the health of a
logical volume and it makes sense to extend this include other health
indicators as well, specifically:
'm'ismatches: Indicates that there are discrepancies in a RAID
LV. This character is shown after a scrubbing
operation has detected that portions of the RAID
are not coherent.
'r'efresh : Indicates that a device in a RAID array has suffered
a failure and the kernel regards it as failed -
even though LVM can read the device label and
considers the device to be ok. The LV should be
'r'efreshed to notify the kernel that the device is
now available, or the device should be 'r'eplaced
if it is suspected of failing.
...to not pollute the common and format-independent code in the
abstraction layer above.
The format1 pv_write has common code for writing metadata and
PV header by calling the "write_disks" fn and when rewriting
the header itself only (e.g. just for the purpose of changing
the PV UUID) during the pvchange operation, we had to tweak
this functionality for the format1 case and we had to assign
the PV the orphan state temporarily.
This patch removes the need for this format1 tweak and it calls
the write_disks with appropriate flag indicating whether this is
a PV write call or a VG write call, allowing for metatada update
for the latter one.
Also, a side effect of the former tweak was that it effectively
invalidated the cache (even for the non-format1 PVs) as we
assigned it the orphan state temporarily just for the format1
PV write to pass.
Also, that tweak made it difficult to directly detect whether
a PV was part of a VG or not because the state was incorrect.
Also, it's not necessary to backup and restore some PV fields
when doing a PV write:
orig_pe_size = pv_pe_size(pv);
orig_pe_start = pv_pe_start(pv);
orig_pe_count = pv_pe_count(pv);
...
pv_write(pv)
...
pv->pe_size = orig_pe_size;
pv->pe_start = orig_pe_start;
pv->pe_count = orig_pe_count;
...this is already done by the layer below itself (the _format1_pv_write fn).
So let's have this cleaned up so we don't need to be bothered
about any 'format1 special case for pv_write' anymore.
Add basic support for converting LV into an external origin volume.
Syntax:
lvconvert --thinpool vg/pool --originname renamed_origin -T origin
It will convert volume 'origin' into a thin volume, which will
use 'renamed_origin' as an external read-only origin.
All read/write into origin will go via 'pool'.
renamed_origin volume is read-only volume, that could be activated
only in read-only mode, and cannot be modified.
Reorder activation code to look similar for preload tree and
activation tree.
Its also give much better suppport for device stacking,
since now we also support activation of snapshot which might
be then used for other devices.
A new function (dm_tree_node_force_identical_table_reload) was added to
avoid the suppression of identical table reloads. This allows RAID LVs
to reload the on-disk superblock information that contains which devices
have failed and the bitmaps. If the failed device has returned, this has
the effect of restoring the device and initiating recovery. Without this
patch, the user had to completely deactivate their RAID LV and re-activate
it in order to restore the failed device. Now they simply need to
suspend and resume (which is done by 'lvchange --refresh').
The identical table suppression is only avoided if the LV is not PARTAIL
(i.e. all of it's devices can be seen and read by LVM) and the kernel
status of the array contains failed devices. In other words, the function
will only be called in the case where we may have success in restoring
a failed device in the array.
When there are missing PVs in a volume group, most operations that alter
the LVM metadata are disallowed. It turns out that 'vgimport' is one of
those disallowed operations. This is bad because it creates a circular
dependency. 'vgimport' will complain that the VG is inconsistent and that
'vgreduce --removemissing' must be run. However, 'vgreduce' cannot be run
because it has not been imported. Therefore, 'vgimport' must be one of
the operations allowed to change the metadata when PVs are missing. The
'--force' option is the way to make 'vgimport' happen in spite of the
missing PVs.
If zero metadata copies are used, there's no further recalculation of
PV alignment that happens when adding metadata areas to the PV and
which actually calculates the alignment correctly as a matter of fact.
So fix this for "PV without MDA" case as well.
Before this patch:
[1] raw/~ # pvcreate --dataalignment 8m --dataalignmentoffset 4m
--metadatacopies 1 /dev/sda
Physical volume "/dev/sda" successfully created
[1] raw/~ # pvs -o pv_name,pe_start
PV 1st PE
/dev/sda 12.00m
[1] raw/~ # pvcreate --dataalignment 8m --dataalignmentoffset 4m
--metadatacopies 0 /dev/sda
Physical volume "/dev/sda" successfully created
[1] raw/~ # pvs -o pv_name,pe_start
PV 1st PE
/dev/sda 8.00m
After this patch:
[1] raw/~ # pvcreate --dataalignment 8m --dataalignmentoffset 4m
--metadatacopies 1 /dev/sda
Physical volume "/dev/sda" successfully created
[1] raw/~ # pvs -o pv_name,pe_start
PV 1st PE
/dev/sda 12.00m
[1] raw/~ # pvcreate --dataalignment 8m --dataalignmentoffset 4m
--metadatacopies 0 /dev/sda
Physical volume "/dev/sda" successfully created
[1] raw/~ # pvs -o pv_name,pe_start
PV 1st PE
/dev/sda 12.00m
Also, remove a superfluous condition "pv->pe_start < pv->pe_align" in:
if (pe_start == PV_PE_START_CALC && pv->pe_start < pv->pe_align)
pv->pe_start = pv->pe_align ...
This part of the condition is not reachable as with the PV_PE_START_CALC,
we always have pv->pe_start set to 0 from the PV struct initialisation
(...the pv->pe_start value is just being calculated).
When a device fails, we may wish to replace those segments with an
error segment. (Like when a 'vgreduce --removemissing' removes a
failed device that happens to be a RAID image/meta.) We are then left
with images that we will eventually want to remove or replace.
This patch allows us to pull out these virtual "error" sub-LVs. This
allows a user to 'lvconvert -m -1 vg/lv' to extract the bad sub-LVs.
Sub-LVs with error segments are considered for extraction before other
possible devices so that good devices are not accidentally removed.
This patch also adds the ability to replace RAID images that contain error
segments. The user will still be unable to run 'lvconvert --replace'
because there is no way to address the 'error' segment (i.e. no PV
that it is associated with). However, 'lvconvert --repair' can be
used to replace the image's error segment with a new PV. This is also
the most appropriate way to do it, since the LV will continue to be
reported as 'partial'.
Currently it is impossible to remove a failed PV which has a RAID LV
on it. This patch fixes the issue by replacing the failed PV with an
'error' segment within the affected sub-LVs. Once there is no longer
a RAID LV using the PV, it can be removed.
Most often, it is better to replace a failed RAID device with a spare.
(You can use 'lvconvert --repair <vg>/<LV>' to accomplish that.)
However, if there are no spares in the volume group and none will be
added, it is useful to be able to removed the failed device.
Following patches address the ability to perform 'lvconvert' operations
on RAID LVs that contain sub-LVs composed of 'error' segments.
We have been using 'mirror_region_size' in lvm.conf as the default region
size for RAID logical volumes as well as mirror logical volumes. Since,
"raid" is more inclusive and representative than "mirror", I have changed
the name of this setting. We must still check for the old setting and warn
the user if we are overriding it with the new setting if both happen to be
present.
Instead of check for lv_is_active() for thin pool LV,
query the whole pool via new pool_is_active().
Fixes a problem when we cannot change discards settings
for active pool device where the actual layer for pool
device was inactive, but thin volumes using thin pool
have been active.
This internal function check for active pool device.
For cluster it checks every thin volume,
On the non-clustered VG we need to check just
for presence of -tpool device.
There are currently a few issues with the reporting done on RAID LVs and
sub-LVs. The most concerning is that 'lvs' does not always report the
correct failure status of individual RAID sub-LVs (devices). This can
occur when a device fails and is restored after the failure has been
detected by the kernel. In this case, 'lvs' would report all devices are
fine because it can read the labels on each device just fine.
Example:
[root@bp-01 lvm2]# lvs -a -o name,vg_name,attr,copy_percent,devices vg
LV VG Attr Cpy%Sync Devices
lv vg rwi-a-r-- 100.00 lv_rimage_0(0),lv_rimage_1(0)
[lv_rimage_0] vg iwi-aor-- /dev/sda1(1)
[lv_rimage_1] vg iwi-aor-- /dev/sdb1(1)
[lv_rmeta_0] vg ewi-aor-- /dev/sda1(0)
[lv_rmeta_1] vg ewi-aor-- /dev/sdb1(0)
However, 'dmsetup status' on the device tells us a different story:
[root@bp-01 lvm2]# dmsetup status vg-lv
0 1024000 raid raid1 2 DA 1024000/1024000
In this case, we must also be sure to check the RAID LVs kernel status
in order to get the proper information. Here is an example of the correct
output that is displayed after this patch is applied:
[root@bp-01 lvm2]# lvs -a -o name,vg_name,attr,copy_percent,devices vg
LV VG Attr Cpy%Sync Devices
lv vg rwi-a-r-p 100.00 lv_rimage_0(0),lv_rimage_1(0)
[lv_rimage_0] vg iwi-aor-p /dev/sda1(1)
[lv_rimage_1] vg iwi-aor-- /dev/sdb1(1)
[lv_rmeta_0] vg ewi-aor-p /dev/sda1(0)
[lv_rmeta_1] vg ewi-aor-- /dev/sdb1(0)
The other case where 'lvs' gives incomplete or improper output is when a
device is replaced or added to a RAID LV. It should display that the RAID
LV is in the process of sync'ing and that the new device is the only one
that is not-in-sync - as indicated by a leading 'I' in the Attr column.
(Remember that 'i' indicates an (i)mage that is in-sync and 'I' indicates
an (I)mage that is not in sync.) Here's an example of the old incorrect
behaviour:
[root@bp-01 lvm2]# lvs -a -o name,vg_name,attr,copy_percent,devices vg
LV VG Attr Cpy%Sync Devices
lv vg rwi-a-r-- 100.00 lv_rimage_0(0),lv_rimage_1(0)
[lv_rimage_0] vg iwi-aor-- /dev/sda1(1)
[lv_rimage_1] vg iwi-aor-- /dev/sdb1(1)
[lv_rmeta_0] vg ewi-aor-- /dev/sda1(0)
[lv_rmeta_1] vg ewi-aor-- /dev/sdb1(0)
[root@bp-01 lvm2]# lvconvert -m +1 vg/lv; lvs -a -o name,vg_name,attr,copy_percent,devices vg
LV VG Attr Cpy%Sync Devices
lv vg rwi-a-r-- 0.00 lv_rimage_0(0),lv_rimage_1(0),lv_rimage_2(0)
[lv_rimage_0] vg Iwi-aor-- /dev/sda1(1)
[lv_rimage_1] vg Iwi-aor-- /dev/sdb1(1)
[lv_rimage_2] vg Iwi-aor-- /dev/sdc1(1)
[lv_rmeta_0] vg ewi-aor-- /dev/sda1(0)
[lv_rmeta_1] vg ewi-aor-- /dev/sdb1(0)
[lv_rmeta_2] vg ewi-aor-- /dev/sdc1(0) ** Note that all the images currently are marked as 'I' even though it is
only the last device that has been added that should be marked.
Here is an example of the correct output after this patch is applied:
[root@bp-01 lvm2]# lvs -a -o name,vg_name,attr,copy_percent,devices vg
LV VG Attr Cpy%Sync Devices
lv vg rwi-a-r-- 100.00 lv_rimage_0(0),lv_rimage_1(0)
[lv_rimage_0] vg iwi-aor-- /dev/sda1(1)
[lv_rimage_1] vg iwi-aor-- /dev/sdb1(1)
[lv_rmeta_0] vg ewi-aor-- /dev/sda1(0)
[lv_rmeta_1] vg ewi-aor-- /dev/sdb1(0)
[root@bp-01 lvm2]# lvconvert -m +1 vg/lv; lvs -a -o name,vg_name,attr,copy_percent,devices vg
LV VG Attr Cpy%Sync Devices
lv vg rwi-a-r-- 0.00 lv_rimage_0(0),lv_rimage_1(0),lv_rimage_2(0)
[lv_rimage_0] vg iwi-aor-- /dev/sda1(1)
[lv_rimage_1] vg iwi-aor-- /dev/sdb1(1)
[lv_rimage_2] vg Iwi-aor-- /dev/sdc1(1)
[lv_rmeta_0] vg ewi-aor-- /dev/sda1(0)
[lv_rmeta_1] vg ewi-aor-- /dev/sdb1(0)
[lv_rmeta_2] vg ewi-aor-- /dev/sdc1(0)
** Note only the last image is marked with an 'I'. This is correct and we can
tell that it isn't the whole array that is sync'ing, but just the new
device.
It also works under snapshots...
[root@bp-01 lvm2]# lvs -a -o name,vg_name,attr,copy_percent,devices vg
LV VG Attr Cpy%Sync Devices
lv vg owi-a-r-p 33.47 lv_rimage_0(0),lv_rimage_1(0),lv_rimage_2(0)
[lv_rimage_0] vg iwi-aor-- /dev/sda1(1)
[lv_rimage_1] vg Iwi-aor-p /dev/sdb1(1)
[lv_rimage_2] vg Iwi-aor-- /dev/sdc1(1)
[lv_rmeta_0] vg ewi-aor-- /dev/sda1(0)
[lv_rmeta_1] vg ewi-aor-p /dev/sdb1(0)
[lv_rmeta_2] vg ewi-aor-- /dev/sdc1(0)
snap vg swi-a-s-- /dev/sda1(51201)
If there was a nested mountpoint inside an existing mount path,
blkdeactivate could fail to unmount such a mountpoint as it
needs to deactivate the deepest path first and continue upwards.
For example the simplest reproducer:
[root@rhel6-a ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 4G 0 disk
|-vg-lvol0 (dm-2) 253:2 0 32M 0 lvm /mnt/a
`-vg-lvol1 (dm-3) 253:3 0 32M 0 lvm /mnt/a/b
Before this patch:
[root@rhel6-a ~]# blkdeactivate -u
Deactivating block devices:
UMOUNT: unmounting vg-lvol0 (dm-2) mounted on /mnt/a
umount: /mnt/a: device is busy.
(In some cases useful info about processes that use
the device is found by lsof(8) or fuser(1))
UMOUNT: unmounting vg-lvol1 (dm-3) mounted on /mnt/a/b
LVM: deactivating Logical Volume vg/lvol1
(deactivation of vg/lvol0 is skipped as /mnt/a that is on lvol0
can't be unmounted - it still has /mnt/a/b as nested mountpoint!)
With this patch applied:
[root@rhel6-a ~]# blkdeactivate -u
Deactivating block devices:
UMOUNT: unmounting vg-lvol1 (dm-3) mounted on /mnt/a/b
UMOUNT: unmounting vg-lvol0 (dm-2) mounted on /mnt/a
LVM: deactivating Logical Volume vg/lvol0
LVM: deactivating Logical Volume vg/lvol1
===
Also, this patch contains a fix for processing mangled mount paths:
[root@rhel6-a ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 4G 0 disk
`-vg-lvol0 (dm-2) 253:2 0 32M 0 lvm /mnt/x y z
[root@rhel6-a ~]# lsblk -r
vg-lvol0 253:2 0 32M 0 lvm /mnt/x\x20y\x20z
(the mount path is mangled with \xNN that is visible in raw
lsblk output only and which is used in blkdeactive as well)
Before this patch:
[root@rhel6-a ~]# blkdeactivate -u
Deactivating block devices:
umount: /mnt/x\x20y\x20z: not found
After this patch applied:
[root@rhel6-a ~]# blkdeactivate -u
Deactivating block devices:
UMOUNT: unmounting vg-lvol0 (dm-2) mounted on /mnt/x\x20y\x20z
LVM: deactivating Logical Volume vg/lvol0
For reseting locale environment into significantly less memory
consuming version 'C' - use LC_ALL instead of LANG since it has
higher priority in locale settings.
Otherwise we may observe whole locale-archive which might be
over 100MB on i.e. Fedora systems locked in memory with
some daemons.
Add log/debug_classes to lvm.conf to allow debug messages to be
classified and filtered at runtime.
The dm_errno field is only used by log_error(), so I've redefined it
for log_debug() messages to hold the message class.
By default, all existing messages appear, but we can add categories that
generate high volumes of data, such as logging all traffic to/from
lvmetad.
We need to call sync_local_dev_names directly as pvscan uses
VG_GLOBAL lock and this one *does not* cause the synchronization
(sync_dev_names) to be called on unlock (VG_GLOBAL is not a real VG):
define unlock_vg(cmd, vol)
do { \
if (is_real_vg(vol)) \
sync_dev_names(cmd); \
(void) lock_vol(cmd, vol, LCK_VG_UNLOCK); \
} while (0)
Without this fix, we end up without udev synchronization for the
pvscan --cache (mainly for -aay that causes the VGs/LVs to be
autoactivated) and also udev synchronization cookies are then left
in the system since they're not managed properly (code before sets
up udev sync cookies, but we have to call dm_udev_wait at least once
after that to do the wait and cleanup).
Before, the pvscan --cache -aay was called on each ADD and CHANGE
uevent (for a device that is not a device-mapper device) and each CHANGE
event (for a PV that is a device-mapper device).
This causes troubles with autoactivation in some cases as CHANGE event
may originate from using the OPTION+="watch" udev rule that is defined
in 60-persistent-storage.rules (part of the rules provided by udev
directly) and it's used for all block devices
(except fd*|mtd*|nbd*|gnbd*|btibm*|dm-*|md* devices). For example, the
following sequence incorrectly activates the rest of LVs in a VG if one
of the LVs in the VG is being removed:
[root@rhel6-a ~]# pvcreate /dev/sda
Physical volume "/dev/sda" successfully created
[root@rhel6-a ~]# vgcreate vg /dev/sda
Volume group "vg" successfully created
[root@rhel6-a ~]# lvcreate -l1 vg
Logical volume "lvol0" created
[root@rhel6-a ~]# lvcreate -l1 vg
Logical volume "lvol1" created
[root@rhel6-a ~]# vgchange -an vg
0 logical volume(s) in volume group "vg" now active
[root@rhel6-a ~]# lvs
LV VG Attr LSize Pool Origin Data% Move Log
Cpy%Sync Convert
lvol0 vg -wi------ 4.00m
lvol1 vg -wi------ 4.00m
[root@rhel6-a ~]# lvremove -ff vg/lvol1
Logical volume "lvol1" successfully removed
[root@rhel6-a ~]# lvs
LV VG Attr LSize Pool Origin Data% Move Log
Cpy%Sync Convert
lvol0 vg -wi-a---- 4.00m
...so the vg was deactivated, then lvol1 removed, and we end up with
lvol1 removed (which is ok) BUT with lvol0 activated (which is wrong)!!!
This is because after lvol1 removal, we need to write metadata to the
underlying device /dev/sda and that causes the CHANGE event to be
generated (because of the WATCH udev rule set on this device) and this
causes the pvscan --cache -aay to be reevaluated.
We have to limit this and call pvscan --cache -aay to autoactivate
VGs/LVs only in these cases:
--> if the *PV is not a dm device*, scan only after proper device
addition (ADD event) and not with any other changes (CHANGE event)
--> if the *PV is a dm device*, scan only after proper mapping
activation (CHANGE event + the underlying PV in a state "just
activated")
If a RAID array is not in-sync, replacing devices should not be allowed
as a general rule. This is because the contents used to populate the
incoming device may be undefined because the devices being read where
not in-sync. The kernel enforces this rule unless overridden by not
allowing the creation of an array that is not in-sync and includes a
devices that needs to be rebuilt.
Since we cannot know the sync state of an LV if it is inactive, we must
also enforce the rule that an array must be active to replace devices.
That leaves us with the following conditions:
1) never allow replacement or repair of devices if the LV is in-active
2) never allow replacement if the LV is not in-sync
3) allow repair if the LV is not in-sync, but warn that contents may
not be recoverable.
In the case where a user is performing the repair on the command line via
'lvconvert --repair', the warning is printed before the user is prompted
if they would like to replace the device(s). If the repair is automated
(i.e. via dmeventd and policy is "allocate"), then the device is replaced
if possible and the warning is printed.
If the lvmcache_info_from_pvid() fails to find valid
info, invoke the lookup by dev, and only in this case
call lvmcache_info_from_pvid() again.
Also check for the result of info and return
error directly, so the NULL is not passed
to lvmcache_get_label().
If we fail to get memory for mutex, hash the mutex
or fail somewhere along pthread function calls
return allocated resources back and unlock vg_lock_map mutex.
Detect failure of dm_pool_strdup() and print error in fail path.
Save one extra strchr call - since we already know the distance
for the '=' character.
Drop stack trace from return after log_error().
When the abort_on_internal_errors is enabled, we aborted prior
the syslog logging output.
Since such fatal error gets level _LOG_FATAL it should
not be blocked by debug_level() check so lets move it further,
to get abort error logged also via syslog.
Tabify
Remove use of asize, unneeded.
Don't initialize lvobj->parent_vgobj to NULL, the object ctor already
zeroed everything on alloc.
Redo call to lvm_lv_snapshot to use the liblvm snapshot implementation
we went with.
Add {}s to silence warning in lv_dealloc.
Rename snapshot function for consistency.
Update WHATS_NEW.
Signed-off-by: Andy Grover <agrover@redhat.com>
Function _ignore_blocked_mirror_devices was not release
allocated strings images_health and log_health.
In error paths it was also not releasing dm_task structure.
Swaped return code of _ignore_blocked_mirror_devices and
use 1 as success.
In _parse_mirror_status use log_error if memory allocation
fails and few more errors so they are no going unnoticed
as debug messages.
On error path always clear return values and free strings.
For dev_create_file use cache mem pool to avoid memleak.
Attempting pvmove on RAID LVs replaces the kernel RAID target with
a temporary pvmove target, ultimately destroying the RAID LV. pvmove
must be prevented on RAID LVs for now.
Use 'lvconvert --replace old_pv vg/lv new_pv' if you want to move
an image of the RAID LV.
In case we don't want to activate, autoactivate or have the
VG/LV read-only. Primarily targeted for the auto_activation_volume_list,
but it makes no harm for other settings (the part of the code
that reads these three settings is shared, but there's no
reason to separate it only for this change).
Rework thin feature detection to support runtime
section to allow to disable them selectively.
New lvm.conf option is born: global/thin_disabled_features
Support swapping of metadata device if the thin pool already
exists. This way it's easy to i.e. resize metadata or their
repair operation.
User may create some empty LV, replace existing metadata
or dump and restore them into bigger LV.
Setting this environment variable will cause a full fallback
to old direct node and symlink management in libdevmapper and lvm2.
It means:
- disabling udev synchronization
(--noudevsync in dmsetup and --noudevsync + activation/udev_sync=0
lvm2 config)
- disabling dm and any subsystem related udev rules
(--noudevrules in dmsetup and activation/udev_rules=0 lvm2 config)
- management of nodes/symlinks under /dev directly by libdevmapper/lvm2
(--verifyudev in dmsetup and activation/verify_udev_operations=1
lvm2 config)
- not obtaining any device list from udev database
(devices/obtain_device_list_from_udev=0 lvm2 config)
Note: we could set all of these before - there's no functional change!
However the DM_DISABLE_UDEV environment variable is a nice shortcut
to make it easier for libdevmapper users so that one can switch off all
of the udev management off at one go directly on the command line,
without a need to modify any source or add any extra switches.
If udev synchronization is disabled by means of --noudevsync
option, we should disable just the synchronization and nothing else.
The udev fallback (verifying udev operations and fixing the
nodes/symlinks if found incorrect) is orthogonal and controlled
by a separate activation/verify_udev_operations configuration option.
Allow restoring metadata with thin pool volumes.
No validation is done for this case within vgcfgrestore tool -
thus incorrect metadata may lead to destruction of pool content.
Configurable settings for thin pool create
if they are not specified on command line.
New supported lvm.conf options are:
allocation/thin_pool_chunk_size
allocation/thin_pool_discards
allocation/thin_pool_zero
Check if target supports discards for chunk sizes,
that are not power of 2 (just multiple of 64K),
and enable it in case it's supported by thin kernel target.
Similar to the way the 'mirror', 'raid1' and 'raid10' segment types set
the number of mirrors to 2 ('-m 1') if the argument is not specified,
here we set the number of stripes to 2 if not given on the command line
when creating a RAID10 LV.
Move common functions for lvcreate and lvconvert.
get_pool_params() - read thin pool args.
update_pool_params() - updates/validates some thin args.
It is getting complicated and even few more things will be
implemented, so to avoid reimplementing things differently
in lvcreate and lvconvert code has been splitted
into 2 common functions that allow some future extension.
This patch is intended to fix bug 825323 - FS turns read-only during a double
fault of a mirror leg and mirrored log's leg at the same time. It only
affects a 2-way mirror with a mirrored log. 3+-way mirrors and mirrors
without a mirrored log are not affected.
The problem resulted from the fact that the top level mirror was not
using 'noflush' when suspending before its "down-convert". When a
mirror image fails, the bios are queue until a suspend is recieved. If
it is a 'noflush' suspend, the bios can be safely requeued in the DM
core. If 'noflush' is not used, the bios must be pushed through the
target and if a device is failed for a mirror, that means issuing an
error. When an error is received by a file system, it results in it
turning read-only (depending on the FS).
Part of the problem was is due to the nature of the stacking involved in
using a mirror as a mirror's log. When an image in each fail, the top
level mirror stalls because it is waiting for a log flush. The other
stalls waiting for corrective action. When the repair command is issued,
the entire stacked arrangement is collapsed to a linear LV. The log
flush then fails (somewhat uncleanly) and the top-level mirror is suspended
without 'noflush' because it is a linear device.
This patch allows the log to be repaired first, which in turn allows the
top-level mirror's log flush to complete cleanly. The top-level mirror
is then secondarily reduced to a linear device - at which time this mirror
is suspended properly with 'noflush'.
Don't use lvmetad in lvm2-monitor.service ExecStop to avoid a systemd issue.
- a systemd design issue while processing dependencies
with socket-based activation that ends up with a hang
- https://bugzilla.redhat.com/show_bug.cgi?id=843587
(also tracker bug https://bugzilla.redhat.com/show_bug.cgi?id=871527)
- not using lvmetad in this case is just a workaround, once the bug
above is resolved, we should enable the lvmetad in that specific case
Remove dependency on fedora-storage-init.service in lvm2 systemd units.
- fedora-storage-init.service and fedora-storage-init-late.service is
going to be separated into respective units that belong to each block
device subsystem:
- mpath + mdraid activated via udev solely
- dmraid with its own dmraid-activation.service unit
- lvm2 with the lvm2-activation-generator to generate the
activation units runtime if lvmetad disabled
(global/use_lvmetad=0 set in lvm.conf) and activation done
via udev+lvmetad if lvmetad enabled (global/use_lvmetad=1 set
in lvm.conf)
Depend on lvm2-lvmetad.socket in lvm2-monitor.service systemd unit.
- as lvm2-monitor uses lvmetad if lvmetad is enabled
Commit 9fd7ac7d03 did not handle mirrors
that contained mirrored logs. This is because the status line of the
mirror does not give an indication of the health of the mirrored log,
as you can see here:
[root@bp-01 lvm2]# dmsetup status vg-lv vg-lv_mlog
vg-lv: 0 409600 mirror 2 253:6 253:7 400/400 1 AA 3 disk 253:5 A
vg-lv_mlog: 0 8192 mirror 2 253:3 253:4 7/8 1 AD 1 core
Thus, the possibility for LVM commands to hang still persists when mirror
have mirrored logs. I discovered this while performing some testing that
does polling with 'pvs' while doing I/O and killing devices. The 'pvs'
managed to get between the mirrored log device failure and the attempt
by dmeventd to repair it. The result was a very nasty block in LVM
commands that is very difficult to remove - even for someone who knows
what is going on. Thus, it is absolutely essential that the log of a
mirror be recursively checked for mirror devices which may be failed
as well.
Despite what the code comment says in the aforementioned commit...
+ * _mirrored_transient_status(). FIXME: It is unable to handle mirrors
+ * with mirrored logs because it does not have a way to get the status of
+ * the mirror that forms the log, which could be blocked.
... it is possible to get the status of the log because the log device
major/minor is given to us by the status output of the top-level mirror.
We can use that to query the log device for any DM status and see if it
is a mirror that needs to be bypassed. This patch does just that and is
now able to avoid reading from mirrors that have failed devices in a
mirrored log.
Addresses: rhbz855398 (Allow VGs to be built on cluster mirrors),
and other issues.
The LVM code attempts to avoid reading labels from devices that are
suspended to try to avoid situations that may cause the commands to
block indefinitely. When scanning devices, 'ignore_suspended_devices'
can be set so the code (lib/activate/dev_manager.c:device_is_usable())
checks any DM devices it finds and avoids them if they are suspended.
The mirror target has an additional mechanism that can cause I/O to
be blocked. If a device in a mirror fails, all I/O will be blocked
by the kernel until a new table (a linear target or a mirror with
replacement devices) is loaded. The mirror indicates that this condition
has happened by marking a 'D' for the faulty device in its status
output. This condition must also be checked by 'device_is_usable()' to
avoid the possibility of blocking LVM commands indefinitely due to an
attempt to read the blocked mirror for labels.
Until now, mirrors were avoided if the 'ignore_suspended_devices'
condition was set. This check seemed to suggest, "if we are concerned
about suspended devices, then let's ignore mirrors altogether just
in case". This is insufficient and doesn't solve any problems. All
devices that are suspended are already avoided if
'ignore_suspended_devices' is set; and if a mirror is blocking because
of an error condition, it will block the LVM command regardless of the
setting of that variable.
Rather than avoiding mirrors whenever 'ignore_suspended_devices' is
set, this patch causes mirrors to be avoided whenever they are blocking
due to an error. (As mentioned above, the case where a DM device is
suspended is already covered.) This solves a number of issues that weren't
handled before. For example, pvcreate (or any command that does a
pv_read or vg_read, which eventually call device_is_usable()) will be
protected from blocked mirrors regardless of how
'ignore_suspended_devices' is set. Additionally, a mirror that is
neither suspended nor blocking is /allowed/ to be read regardless
of how 'ignore_suspended_devices' is set. (The latter point being the
source of the fix for rhbz855398.)
clvmd -d option parsing was not working properly.
clvmd -d 2 (with space) has been ignored because of
'::' used in getopt string, and as failsafe it's been used '1'.
Later this debug_arg has been ignored and debug_opt was used
instead which happend to have value '1'.
Submitted-by: Robert Milasan <rmilasan at suse.com>
Reported-by: Robert Milasan <rmilasan at suse.com>
Use log_warn to print non-fatal warning messages.
Use of log_error would confuse checker for testing
whether proper error has been reported for some real error.
Try to bring the lvmetad usage text and man page closer to the code.
There seem to be 3 useful ways to use -d with lvmetad at the moment:
-d all
-d wire
-d debug
(They can also be comma-separated like -d wire,debug.)
Prior to the last release, -d, -dd and -ddd were supported.
Fail if an unrecognised debug arg is supplied on the command line.
Change -V to report the same version as the lvm binary: previously it
just reported version 0.
Use configure --enable-python_bindings to generate them.
Note that the Makefiles do not yet control the owner or permissions of
the two new files on installation.
A while back, the behavior of LVM changed from allowing metadata changes
when PVs were missing to not allowing changes. Until recently, this
change was tolerated by HA-LVM by forcing a 'vgreduce --removemissing'
before trying (again) to add tags to an LV and then activate it. LVM
mirroring requires that failed devices are removed anyway, so this was
largely harmless. However, RAID LVs do not require devices to be removed
from the array in order to be activated. In fact, in an HA-LVM
environment this would be very undesirable. Device failures in such an
environment can often be transient and it would be much better to restore
the device to the array than synchronize an entirely new device.
There are two methods that can be used to setup an HA-LVM environment:
"clvm" or "tagging". For RAID LVs, "clvm" is out of the question because
RAID LVs are not supported in clustered VGs - not even in an exclusively
activated manner. That leaves "tagging". HA-LVM uses tagging - coupled
with 'volume_list' - to ensure that only one machine can have an LV active
at a time. If updates are not allowed when a PV is missing, it is
impossible to add or remove tags to allow for activation. This removes
one of the most basic functionalities of HA-LVM - site redundancy. If
mirroring or RAID is used to replicate the storage in two data centers
and one of them goes down, a server and a storage device are lost. When
the service fails-over to the alternate site, the VG will be "partial".
Unable to add a tag to the VG/LV, the RAID device will be unable to
activate.
The solution is to allow vgchange and lvchange to alter the LVM metadata
for a limited set of options - --[add|del]tag included. The set of
allowable options are ones that do not cause changes to the DM kernel
target (like --resync would) or could alter the structure of the LV
(like allocation or conversion).
The ExecStartPost with pvscan --cache in lvm2-lvmetad.service
is not needed now as this is called transparently within the
first LVM command that queries lvmetad.
For now this convertions is not supported, thus disabled.
The only supported conversion for now is to create mirrored thin pools
from mirrored devices.
It would be possible to activate a RAID LV exclusively in a cluster
volume group, but for now we do not allow RAID LVs to exist in a
clustered volume group at all. This has two components:
1) Do not allow RAID LVs to be created in a clustered VG
2) Do not allow changing a VG from single-machine to clustered
if there are RAID LVs present.
Update code for lvconvert.
Change the lvconvert user interface a bit - now we require 2 specifiers
--thinpool takes LV name for data device (and makes the name)
--poolmetadata takes LV name for metadata device.
Fix type in thin help text -z -> -Z.
Supported is also new flag --discards for thinpools.
MD's bitmaps can handle 2^21 regions at most. The RAID code has always
used a region_size of 1024 sectors. That means the size of a RAID LV was
limited to 1TiB. (The user can adjust the region_size when creating a
RAID LV, which can affect the maximum size.) Thus, creating, extending or
converting to a RAID LV greater than 1TiB would result in a failure to
load the new device-mapper table.
Again, the size of the RAID LV is not limited by how much space is allocated
for the metadata area, but by the limitations of the MD bitmap. Therefore,
we must adjust the 'region_size' to ensure that the number of regions does
not exceed the limit. I've added code to do this when extending a RAID LV
(which covers 'create' and 'extend' operations) and when up-converting -
specifically from linear to RAID1.
Don't try to issue discards to a missing PV to avoid segfault.
Prevent lvremove from removing LVs that have any part missing.
https://bugzilla.redhat.com/857554
Failing to clear the LV_NOTSYNCED flag when converting a RAID1 LV to
linear can result in the flag being present after an upconvert - even
if the sync is performed when upconverting.
Mirrors do not allow upconverting if the LV has been created with --nosync.
We will enforce the same rule for RAID1. It isn't hugely critical, since
the portions that have been written will be copied over to the new device
identically from either of the existing images. However, the unwritten
sections may be different, causing the added image to be a hybrid of the
existing images.
Also, we are disallowing the addition of new images to a RAID1 LV that has
not completed the initial sync. This may be different from mirroring, but
that is due to the fact that the 'mirror' segment type "stacks" when adding
a new image and RAID1 does not. RAID1 will rebuild a newly added image
"inline" from the existant images, so they should be in-sync.
The "fedora-wait-storage.service" that the "lvm2-activation.service"
had as a dependency (which was fedora-specific solution anyway)
is obsolete now as this unit called "modprobe scsi_wait_scan"
which is not used anymore.
The "fedora-wait-storage.service" had "systemd-udev-settle" as
its dependency, so let's depend on this one directly now,
bypassing the out-dated "fedora-wait-storage.service".
Using 'activation/auto_activation_volume_list = [ "vg/lvol1" ]'.
Before this patch:
3 logical volume(s) in volume group "vg" now active
LV VG Attr LSize Pool Origin Data% Move Log Copy% Convert
lvol0 vg -wi----- 4.00m
lvol1 vg -wi-a--- 4.00m
lvol2 vg -wi-a--- 4.00m
lvol3 vg -wi-a--- 4.00m
(vg/lvol1 activated as it passes the list and all subsequent volumes too - wrong!)
With this patch:
1 logical volume(s) in volume group "vg" now active
LV VG Attr LSize Pool Origin Data% Move Log Copy% Convert
lvol0 vg -wi----- 4.00m
lvol1 vg -wi-a--- 4.00m
lvol2 vg -wi----- 4.00m
lvol3 vg -wi----- 4.00m
(only vg/lvol1 activated as it passes the list and no other - correct!)
Issuing a 'lvchange --resync <VG>/<RAID_LV>' had no effect. This is
because the code to handle RAID LVs was not present. This patch adds
the code that will clear the metadata areas of RAID LVs - causing them
to resync upon activation.
By changing the conditional for resyncing mirrors with core-logs a
bit, we can short-circuit the rest of the function for that case
and reduce the amount of indenting in the rest of the function.
This cleanup will simplify future patches aimed at properly handling
the resync of RAID LVs.
It is necessary when creating a RAID LV to clear the new metadata areas.
Failure to do so could result in a prepopulated bitmap that would cause
the new array to skip syncing portions of the array. It is a requirement
that the metadata LVs be activated and cleared in the process of creating.
However in test mode, this requirement should be lifted - no new LVs should
be created or written to.
Fix setvbuf code by closing and reopening stream before changing buffer.
But we need to review what this code is doing embedded inside a library
function rather than the simpler original form being run independently
at the top of main() by tools that need it.
Accept -q as the short form of --quiet.
Suppress non-essential standard output if -q is given twice.
Treat log/silent in lvm.conf as equivalent to -qq.
Review all log_print messages and change some to
log_print_unless_silent.
When silent, the following commands still produce output:
dumpconfig, lvdisplay, lvmdiskscan, lvs, pvck, pvdisplay,
pvs, version, vgcfgrestore -l, vgdisplay, vgs.
[Needs checking.]
Non-essential messages are shifted from log level 4 to log level 5
for syslog and lvm2_log_fn purposes.
This patch adds support for RAID10. It is not the default at this
stage. The user needs to specify '--type raid10' if they would like
RAID10 instead of stacked mirror over stripe.
Remove the limit for major and minor number arguments used while specifying
persistent numbers via -My --major <major> --minor <minor> option which
was set to 255 before. Follow the kernel limit instead which is 12 bits
for major and 20 bits for minor number (kernel >= 2.6 and LVM formats
that does not have FMT_RESTRICTED_LVIDS - so still keep the old limit
of 255 for lvm1 format).
Allowing people to add devices to a VG that has PVs missing helps
people avoid the inability to repair RAID LVs in certain cases.
For example, if a user creates a RAID 4/5/6 LV using all of the
available devices in a VG, there will be no spare devices to
repair the LV with if a device should fail. Further, because the
VG is missing a device, new devices cannot be added to allow the
repair. If 'vgreduce --removemissing' were attempted, the
"MISSING" PV could not be removed without also destroying the RAID
LV.
Allowing vgextend to operate solves the circular dependency.
When the PV is added by a vgextend operation, the sequence number is
incremented and the 'MISSING' flag is put on the PVs which are missing.
A regression introduced in 2.02.89 (11e520256b)
caused the lvm dumpconfig <node> to print out
the node as well as its subsequent siblings.
The information about "only_one" mode got lost.
Before this patch (just an example node):
# lvm dumpconfig global/use_lvmetad
use_lvmetad=1
thin_check_executable="/usr/sbin/thin_check"
thin_check_options="-q"
(...all nodes to the end of the section)
With this patch applied:
# lvm dumpconfig global/use_lvmetad
use_lvmetad=1
If a daemon (like lvmetad that is using common daemon-server code)
received a kill signal that was supposed to shut the daemon down,
a spurious message was issued: "Failed to handle a client connection".
This happened if the kill signal came just in the middle of waiting
for a client request in "select" - the request that was supposed to
be handled was blank at that moment of course.
Update lvchange to allow change of 'zero' flag for thinpool.
Add support for changing discard handling.
N.B. from/to ignore could be only changed for inactive pool.
