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Bug 193701

Summary: sync_count is greater than region_count when mirror is fully copied
Product: [Retired] Red Hat Cluster Suite Reporter: Corey Marthaler <cmarthal>
Component: cmirrorAssignee: Jonathan Earl Brassow <jbrassow>
Status: CLOSED CURRENTRELEASE QA Contact: Cluster QE <mspqa-list>
Severity: high Docs Contact:
Priority: high    
Version: 4CC: agk, dwysocha, mbroz
Target Milestone: ---   
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2010-04-27 14:51:26 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 180185    

Description Corey Marthaler 2006-05-31 18:06:27 UTC
Description of problem:
[root@taft-04 sbin]# lvs
  LV        VG       Attr   LSize   Origin Snap%  Move Log            Copy%
  mirror_10 mirror_1 mwi-a- 136.23G                    mirror_10_mlog 100.00
[root@taft-04 sbin]# dmsetup status
mirror_1-mirror_10: 0 285696000 mirror 2 253:3 253:4 279001/279000 1 AA 3
clustered_disk 253:2 A
mirror_1-mirror_10_mlog: 0 8192 linear
VolGroup00-LogVol01: 0 4063232 linear
mirror_1-mirror_10_mimage_1: 0 285696000 linear
VolGroup00-LogVol00: 0 40960000 linear
mirror_1-mirror_10_mimage_0: 0 285696000 linear


From console:
device-mapper: sync_count (279001) > region_count (279000) - this can not be!


Version-Release number of selected component (if applicable):
[root@taft-04 sbin]# rpm -q cmirror-kernel-smp
cmirror-kernel-smp-2.6.9-4.2

Comment 1 Jonathan Earl Brassow 2006-06-02 16:28:16 UTC
What was the command you used to create this volume?  Did you use the '--nosync'
option?


Comment 2 Jonathan Earl Brassow 2006-06-02 16:29:27 UTC
Also, did you do anything besides create the mirror and wait for it to be in-sync?

Comment 3 Corey Marthaler 2006-06-02 19:18:41 UTC
I did not use the --nosync option and I believe that there was possilby a node
recovery senario involved. Attempting to recreate to provide more details... 

Comment 4 Corey Marthaler 2006-06-02 19:36:28 UTC
Finally reproduced this. 

Recovery of a node (not the mirror server is required) and I had to use a 10G
mirror or bigger. Anything 1G or smaller ended up just causing bz 193596.

[root@taft-04 ~]# lvcreate -L 10G -m 1 -n deanmirror mirror_1
  Logical volume "deanmirror" created
[root@taft-04 ~]# lvs
  LV         VG       Attr   LSize  Origin Snap%  Move Log             Copy%
  deanmirror mirror_1 mwi-a- 10.00G                    deanmirror_mlog  16.56
[root@taft-04 ~]# lvscan
  ACTIVE            '/dev/mirror_1/deanmirror' [10.00 GB] inherit
[root@taft-04 ~]#
[root@taft-04 ~]# lvs
  LV         VG       Attr   LSize  Origin Snap%  Move Log             Copy%
  deanmirror mirror_1 mwi-a- 10.00G                    deanmirror_mlog  18.32
[root@taft-04 ~]# lvs
  LV         VG       Attr   LSize  Origin Snap%  Move Log             Copy%
  deanmirror mirror_1 mwi-a- 10.00G                    deanmirror_mlog  23.20


[recover a node (copy starts over at 0.00%)]

[...]
[root@taft-02 ~]# lvs
  LV         VG       Attr   LSize  Origin Snap%  Move Log             Copy%
  deanmirror mirror_1 mwi-a- 10.00G                    deanmirror_mlog  99.53
[root@taft-02 ~]# lvs
  LV         VG       Attr   LSize  Origin Snap%  Move Log             Copy%
  deanmirror mirror_1 mwi-a- 10.00G                    deanmirror_mlog  99.73
[root@taft-02 ~]# lvs
  LV         VG       Attr   LSize  Origin Snap%  Move Log             Copy%
  deanmirror mirror_1 mwi-a- 10.00G                    deanmirror_mlog  99.88
[root@taft-02 ~]# lvs
  LV         VG       Attr   LSize  Origin Snap%  Move Log             Copy%
  deanmirror mirror_1 mwi-a- 10.00G                    deanmirror_mlog 100.00

device-mapper: sync_count (20481) > region_count (20480) - this can not be!


Comment 5 Jonathan Earl Brassow 2006-06-02 22:03:31 UTC
Could you recheck this when the build with fixes for 193706 and 193596 comes
out?  (next build after cmirror-kernel*-2.6.9-4.2)


Comment 7 Corey Marthaler 2006-06-14 20:51:58 UTC
Hit this while attempting to reproduce 193596

Jun 14 09:50:11 taft-03 lvm[4395]: corey-mirror1 is now in-sync
Jun 14 09:50:22 taft-03 lvm[4282]: corey-mirror2 is now in-sync
Jun 14 09:50:22 taft-03 kernel: device-mapper: sync_count (1602) > region_count
(1600) - this can not be!

[root@taft-03 ~]# rpm -q cmirror-kernel
cmirror-kernel-2.6.9-5.4

Comment 8 Corey Marthaler 2006-07-05 22:16:30 UTC
This appears to work now, but just like the verified bz 193596, I now hit bz
195392 which may be a regression.

Comment 10 Alasdair Kergon 2010-04-27 14:51:26 UTC
Assuming this VERIFIED fix got released.  Closing.
Reopen if it's not yet resolved.