Bug 1854558
| Summary: | snapshots of writecache volumes have been enabled | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 8 | Reporter: | Corey Marthaler <cmarthal> |
| Component: | lvm2 | Assignee: | David Teigland <teigland> |
| lvm2 sub component: | Cache Logical Volumes | QA Contact: | cluster-qe <cluster-qe> |
| Status: | CLOSED ERRATA | Docs Contact: | |
| Severity: | medium | ||
| Priority: | high | CC: | agk, heinzm, jbrassow, mcsontos, msnitzer, pasik, prajnoha, teigland, zkabelac |
| Version: | 8.3 | ||
| Target Milestone: | rc | ||
| Target Release: | 8.0 | ||
| Hardware: | x86_64 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | lvm2-2.03.11-0.2.20201103git8801a86.el8 | Doc Type: | If docs needed, set a value |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2021-05-18 15:01:53 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: | |||
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Description
Corey Marthaler
2020-07-07 16:42:13 UTC
The snapshot bug was caused by using the wrong block size which is now fixed (like allowing writecache attach to an active LV.) (In reply to David Teigland from comment #1) > The snapshot bug was caused by using the wrong block size which is now fixed > (like allowing writecache attach to an active LV.) So snapshots have been enabled then? Might want to negotiate that feature with Corey... The implication of fixing the snapshot bug was that we enable snapshots. If we don't want to enable them for other reasons, then that's fine. I'm fine keeping them enabled and have the snapshot tests again turned on. The issue for QA however, was that there was no bug in the current errata that mentioned anything about snapshots or a snapshot bug being fixed. Was this fix added as a part of bug 1630978 or rebase bug 1824209? bug 1630978 comment 6 lists three commits which add fs block size detection (lack of this caused the problem) and enable snapshots. Fix verified in the latest .d rpms. kernel-4.18.0-246.el8.dt2 BUILT: Mon Nov 9 07:22:41 CST 2020 lvm2-2.03.11-0.2.20201103git8801a86.el8 BUILT: Wed Nov 4 07:04:46 CST 2020 lvm2-libs-2.03.11-0.2.20201103git8801a86.el8 BUILT: Wed Nov 4 07:04:46 CST 2020 device-mapper-1.02.175-0.2.20201103git8801a86.el8 BUILT: Wed Nov 4 07:04:46 CST 2020 device-mapper-libs-1.02.175-0.2.20201103git8801a86.el8 BUILT: Wed Nov 4 07:04:46 CST 2020 device-mapper-event-1.02.175-0.2.20201103git8801a86.el8 BUILT: Wed Nov 4 07:04:46 CST 2020 device-mapper-event-libs-1.02.175-0.2.20201103git8801a86.el8 BUILT: Wed Nov 4 07:04:46 CST 2020 SCENARIO - [simple_writecache_snap_merge] Create snaps of writecache origin with fs data, verify data on snaps, change data on origin, merge data back to origin, verify origin data *** Writecache info for this scenario *** * origin (slow): /dev/sdg1 * pool (fast): /dev/sdh1 ************************************ Adding "slow" and "fast" tags to corresponding pvs Create origin (slow) volume lvcreate --yes --wipesignatures y -L 4G -n cworigin writecache_sanity @slow Create writecache cvol (fast) volumes lvcreate --yes -L 2G -n pool writecache_sanity @fast Deactivate *ONLY* fast pool before conversion to write cache (SEE bug 1185347) Create writecached volume by combining the cache pool (fast) and origin (slow) volumes lvconvert --yes --type writecache --cachesettings 'low_watermark=6 high_watermark=84 writeback_jobs=2491 autocommit_blocks=1279 autocommit_time=2334' --cachevol writecache_sanity/pool writecache_sanity/cworigin Placing an xfs filesystem on origin volume Mounting origin volume Writing files to /mnt/cworigin Checking files on /mnt/cworigin Making a snapshot of the origin volume, mounting, and verifying original data ( ** This is again enabled in rhel8.3 ** ) lvcreate --yes -s /dev/writecache_sanity/cworigin -c 64 -n merge -L 500M +++ Mounting and verifying snapshot merge data +++ Checking files on /mnt/merge Writing new origin data and then merging back the snapshot volume Writing files to /mnt/cworigin Checking files on /mnt/cworigin Umount origin volume Deactivating volume: cworigin Merge snapshot writecache_sanity/merge back into the origin lvconvert --yes --merge writecache_sanity/merge Activating volume: cworigin Mount and verify the proper data now exists on the origin Checking files on /mnt/cworigin Fix verified in the latest rpms. kernel-4.18.0-271.el8 BUILT: Fri Jan 8 03:32:43 CST 2021 lvm2-2.03.11-0.4.20201222gitb84a992.el8 BUILT: Tue Dec 22 06:33:49 CST 2020 lvm2-libs-2.03.11-0.4.20201222gitb84a992.el8 BUILT: Tue Dec 22 06:33:49 CST 2020 ============================================================ Iteration 4 of 4 started at Mon Jan 11 12:16:57 CST 2021 ============================================================ SCENARIO - [simple_writecache_snap_merge] Create snaps of writecache origin with fs data, verify data on snaps, change data on origin, merge data back to origin, verify origin data *** Writecache info for this scenario *** * origin (slow): /dev/sdd1 * pool (fast): /dev/sdc1 ************************************ ls: cannot access '/dev/writecache_sanity': No such file or directory Adding "slow" and "fast" tags to corresponding pvs Create origin (slow) volume lvcreate --yes --wipesignatures y -L 4G -n cworigin writecache_sanity @slow Create writecache cvol (fast) volumes lvcreate --yes -L 2G -n pool writecache_sanity @fast Deactivate *ONLY* fast pool before conversion to write cache (SEE bug 1185347) Create writecached volume by combining the cache pool (fast) and origin (slow) volumes lvconvert --yes --type writecache --cachesettings 'low_watermark=32 high_watermark=50 writeback_jobs=1125 autocommit_blocks=2399 autocommit_time=2364' --cachevol writecache_sanity/pool writecache_sanity/cworigin Placing an xfs filesystem on origin volume Mounting origin volume Writing files to /mnt/cworigin Checking files on /mnt/cworigin Making a snapshot of the origin volume, mounting, and verifying original data ( ** This is again enabled in rhel8.3 ** ) lvcreate --yes -s /dev/writecache_sanity/cworigin -c 64 -n merge -L 500M +++ Mounting and verifying snapshot merge data +++ Checking files on /mnt/merge Writing new origin data and then merging back the snapshot volume Writing files to /mnt/cworigin Checking files on /mnt/cworigin Umount origin volume Deactivating volume: cworigin Merge snapshot writecache_sanity/merge back into the origin lvconvert --yes --merge writecache_sanity/merge Activating volume: cworigin Waiting for the snap merge to complete... Mount and verify the proper data now exists on the origin Checking files on /mnt/cworigin Separating cache pool (lvconvert --yes --splitcache writecache_sanity/cworigin) from cache origin Removing cache pool writecache_sanity/pool Removing cache origin volume writecache_sanity/cworigin lvremove -f /dev/writecache_sanity/cworigin Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory (lvm2 bug fix and enhancement update), and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHBA-2021:1659 |