Bug 1029170
| Summary: | request for clarification: does lvm auto repair its corrupted pool tmeta devices | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 6 | Reporter: | Corey Marthaler <cmarthal> |
| Component: | lvm2 | Assignee: | Zdenek Kabelac <zkabelac> |
| Status: | CLOSED NOTABUG | QA Contact: | Cluster QE <mspqa-list> |
| Severity: | medium | Docs Contact: | |
| Priority: | unspecified | ||
| Version: | 6.5 | CC: | agk, dwysocha, heinzm, jbrassow, msnitzer, prajnoha, prockai, thornber, zkabelac |
| Target Milestone: | rc | ||
| Target Release: | --- | ||
| Hardware: | x86_64 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2014-01-28 13:26:41 UTC | Type: | Bug |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
This request was not resolved in time for the current release. Red Hat invites you to ask your support representative to propose this request, if still desired, for consideration in the next release of Red Hat Enterprise Linux. This test is not correct. thin_check is not supposed to be executed on live (active thin pool) metadata volume. Now we have Bug 1023828 (and Bug 1038387), where thin_check should warn before such use. As of current state of tools - lvm2 by default only detects error during activation (and deactivation) via thin_check tool. To actively fix metadata, user should use: lvconvert --repair vg/pool |
Description of problem: I'm attempting to create more test cases for thin_check and thin_repair/thin_restore. However, I'm having a hard time finding a way to reliably corrupt the tmeta device. It appears that lvm is either automatically repairing itself or it's not being truly corrupted in the first place. I've tried with both lvmetad on and off; and both with and with out a spare poolmetadata device. I've also tried corrupting less then 512 bytes, but when I do that it never seems to show up as corrupt. SCENARIO - [recover_corrupt_pool_tmeta_device] Create a snapshot, corrupt it's pool metadata (_tmeta) device, and then restore it using thin_restore Making origin volume lvcreate --thinpool POOL --zero n --poolmetadataspare n -L 1G snapper_thinp WARNING: recovery of pools without pool metadata spare LV is not automated. Sanity checking pool device metadata (thin_check /dev/mapper/snapper_thinp-POOL_tmeta) examining superblock examining devices tree examining mapping tree lvcreate --virtualsize 1G -T snapper_thinp/POOL -n origin lvcreate -V 1G -T snapper_thinp/POOL -n other1 lvcreate --virtualsize 1G -T snapper_thinp/POOL -n other2 lvcreate --virtualsize 1G -T snapper_thinp/POOL -n other3 lvcreate --virtualsize 1G -T snapper_thinp/POOL -n other4 lvcreate --virtualsize 1G -T snapper_thinp/POOL -n other5 Making snapshot of origin volume lvcreate -K -s /dev/snapper_thinp/origin -n restore Dumping current pool metadata to /tmp/snapper_thinp_dump.2180.30275 thin_dump /dev/mapper/snapper_thinp-POOL_tmeta > /tmp/snapper_thinp_dump.2180.30275 Corrupting pool meta device (/dev/mapper/snapper_thinp-POOL_tmeta) dd if=/dev/urandom of=/dev/mapper/snapper_thinp-POOL_tmeta count=512 bs=1 512+0 records in 512+0 records out 512 bytes (512 B) copied, 0.00308854 s, 166 kB/s [root@harding-03 ~]# lvs -a -o +devices LV VG Attr LSize Pool Origin Data% Devices POOL snapper_thinp twi-a-t--- 1.00g 0.04 POOL_tdata(0) [POOL_tdata] snapper_thinp Twi-ao---- 1.00g /dev/sdb3(0) [POOL_tmeta] snapper_thinp ewi-ao---- 4.00m /dev/sdc2(0) origin snapper_thinp Vwi-a-t--- 1.00g POOL 0.01 other1 snapper_thinp Vwi-a-t--- 1.00g POOL 0.01 other2 snapper_thinp Vwi-a-t--- 1.00g POOL 0.01 other3 snapper_thinp Vwi-a-t--- 1.00g POOL 0.01 other4 snapper_thinp Vwi-a-t--- 1.00g POOL 0.01 other5 snapper_thinp Vwi-a-t--- 1.00g POOL 0.01 restore snapper_thinp Vwi-a-t--k 1.00g POOL origin 0.01 [root@harding-03 ~]# thin_check /dev/mapper/snapper_thinp-POOL_tmeta examining superblock superblock is corrupt bad checksum in superblock # And now it's automatically fixed? [root@harding-03 ~]# thin_check /dev/mapper/snapper_thinp-POOL_tmeta examining superblock examining devices tree examining mapping tree # Corrupt it again [root@harding-03 ~]# dd if=/dev/urandom of=/dev/mapper/snapper_thinp-POOL_tmeta count=512 bs=1 512+0 records in 512+0 records out 512 bytes (512 B) copied, 0.00279119 s, 183 kB/s # Corrupt [root@harding-03 ~]# thin_check /dev/mapper/snapper_thinp-POOL_tmeta examining superblock superblock is corrupt bad checksum in superblock # Corrupt [root@harding-03 ~]# thin_check /dev/mapper/snapper_thinp-POOL_tmeta examining superblock superblock is corrupt bad checksum in superblock # Not Corrupt (and all I've done is run this cmd) [root@harding-03 ~]# thin_check /dev/mapper/snapper_thinp-POOL_tmeta examining superblock examining devices tree examining mapping tree # Corrupt it again [root@harding-03 ~]# dd if=/dev/urandom of=/dev/mapper/snapper_thinp-POOL_tmeta count=512 bs=1 512+0 records in 512+0 records out 512 bytes (512 B) copied, 0.00279241 s, 183 kB/s # Run a sync [root@harding-03 ~]# sync # Not Corrupt [root@harding-03 ~]# thin_check /dev/mapper/snapper_thinp-POOL_tmeta examining superblock examining devices tree examining mapping tree [root@harding-03 ~]# lvs -a -o +devices LV VG Attr LSize Pool Origin Data% Devices POOL snapper_thinp twi-a-t--- 1.00g 0.04 POOL_tdata(0) [POOL_tdata] snapper_thinp Twi-ao---- 1.00g /dev/sdb3(0) [POOL_tmeta] snapper_thinp ewi-ao---- 4.00m /dev/sdc2(0) origin snapper_thinp Vwi-a-t--- 1.00g POOL 0.01 other1 snapper_thinp Vwi-a-t--- 1.00g POOL 0.01 other2 snapper_thinp Vwi-a-t--- 1.00g POOL 0.01 other3 snapper_thinp Vwi-a-t--- 1.00g POOL 0.01 other4 snapper_thinp Vwi-a-t--- 1.00g POOL 0.01 other5 snapper_thinp Vwi-a-t--- 1.00g POOL 0.01 restore snapper_thinp Vwi-a-t--k 1.00g POOL origin 0.01 Version-Release number of selected component (if applicable): 2.6.32-424.el6.x86_64 lvm2-2.02.100-8.el6 BUILT: Wed Oct 30 03:10:56 CDT 2013 lvm2-libs-2.02.100-8.el6 BUILT: Wed Oct 30 03:10:56 CDT 2013 lvm2-cluster-2.02.100-8.el6 BUILT: Wed Oct 30 03:10:56 CDT 2013 udev-147-2.50.el6 BUILT: Fri Oct 11 05:58:10 CDT 2013 device-mapper-1.02.79-8.el6 BUILT: Wed Oct 30 03:10:56 CDT 2013 device-mapper-libs-1.02.79-8.el6 BUILT: Wed Oct 30 03:10:56 CDT 2013 device-mapper-event-1.02.79-8.el6 BUILT: Wed Oct 30 03:10:56 CDT 2013 device-mapper-event-libs-1.02.79-8.el6 BUILT: Wed Oct 30 03:10:56 CDT 2013 cmirror-2.02.100-8.el6 BUILT: Wed Oct 30 03:10:56 CDT 2013 How reproducible: Everytime