mirror of
git://sourceware.org/git/lvm2.git
synced 2024-12-21 13:34:40 +03:00
03b0a78640
It's possible for an LVM LV to use a device during activation which then differs from device which LVM assumes based on metadata later on. For example, such device mismatch can occur if LVM doesn't have complete view of devices during activation or if filters are misbehaving or they're incorrectly set during activation. This patch adds code that can detect this mismatch by creating VG UUID and LV UUID index while scanning devices for device cache. The VG UUID index maps VG UUID to a device list. Each device in the list has a device layered above as a holder which is an LVM LV device and for which we know the VG UUID (and similarly for LV UUID index). We can acquire VG and LV UUID by reading /sys/block/<dm_dev_name>/dm/uuid. So these indices represent the actual state of PV device use in the system by LVs and then we compare that to what LVM assumes based on metadata. For example: [0] fedora/~ # lsblk /dev/sdq /dev/sdr /dev/sds /dev/sdt NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sdq 65:0 0 104M 0 disk |-vg-lvol0 253:2 0 200M 0 lvm `-mpath_dev1 253:3 0 104M 0 mpath sdr 65:16 0 104M 0 disk `-mpath_dev1 253:3 0 104M 0 mpath sds 65:32 0 104M 0 disk |-vg-lvol0 253:2 0 200M 0 lvm `-mpath_dev2 253:4 0 104M 0 mpath sdt 65:48 0 104M 0 disk `-mpath_dev2 253:4 0 104M 0 mpath In this case the vg-lvol0 is mapped onto sdq and sds becauset this is what was available and seen during activation. Then later on, sdr and sdt appeared and mpath devices were created out of sdq+sdr (mpath_dev1) and sds+sdt (mpath_dev2). Now, LVM assumes (correctly) that mpath_dev1 and mpath_dev2 are the PVs that should be used, not the mpath components (sdq/sdr, sds/sdt). [0] fedora/~ # pvs Found duplicate PV xSUix1GJ2SK82ACFuKzFLAQi8xMfFxnO: using /dev/mapper/mpath_dev1 not /dev/sdq Using duplicate PV /dev/mapper/mpath_dev1 from subsystem DM, replacing /dev/sdq Found duplicate PV MvHyMVabtSqr33AbkUrobq1LjP8oiTRm: using /dev/mapper/mpath_dev2 not /dev/sds Using duplicate PV /dev/mapper/mpath_dev2 from subsystem DM, ignoring /dev/sds WARNING: Device mismatch detected for vg/lvol0 which is accessing /dev/sdq, /dev/sds instead of /dev/mapper/mpath_dev1, /dev/mapper/mpath_dev2. PV VG Fmt Attr PSize PFree /dev/mapper/mpath_dev1 vg lvm2 a-- 100.00m 0 /dev/mapper/mpath_dev2 vg lvm2 a-- 100.00m 0 |
||
|---|---|---|
| .. | ||
| dev-cache.c | ||
| dev-cache.h | ||
| dev-dasd.c | ||
| dev-ext-udev-constants.h | ||
| dev-ext.c | ||
| dev-io.c | ||
| dev-luks.c | ||
| dev-md.c | ||
| dev-swap.c | ||
| dev-type.c | ||
| dev-type.h | ||
| device-types.h | ||
| device.h | ||