Bug 252016

Summary: LVM2 counts mirror subdevices as logical volumes
Product: Red Hat Enterprise Linux 4 Reporter: Nate Straz <nstraz>
Component: lvm2Assignee: Alasdair Kergon <agk>
Status: CLOSED ERRATA QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: 4.5CC: dwysocha, jbrassow, mbroz
Target Milestone: ---   
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: RHBA-2008-0776 Doc Type: Bug Fix
Doc Text:
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Clone Of: Environment:
Last Closed: 2008-07-24 20:07:28 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:

Description Nate Straz 2007-08-13 19:47:17 UTC 
Description of problem:

When a mirror volume exists, the number of logical volumes that `vgs` displays
is equal to the number of device mapper devices instead of the number of logical
volumes.

Version-Release number of selected component (if applicable):
lvm2-2.02.21-5.el4
lvm2-cluster-2.02.21-7.el4


How reproducible:
100%

Steps to Reproduce:
1. lvcreate -m 2 -n mirror vgname
2. vgs
  
Actual results:

[root@tank-01 ~]# vgs
  VG           #PV #LV #SN Attr   VSize   VFree  
  VolGroup00     1   2   0 wz--n-  37.16G  64.00M
  tank-cluster   4   5   0 wz--nc 915.70G 615.70G
[root@tank-01 ~]# lvs
  LV       VG           Attr   LSize   Origin Snap%  Move Log         Copy% 
  LogVol00 VolGroup00   -wi-ao  35.16G                                      
  LogVol01 VolGroup00   -wi-ao   1.94G                                      
  mirror   tank-cluster mwi-ao 100.00G                    mirror_mlog  10.29
[root@tank-01 ~]# dmsetup ls
tank--cluster-mirror    (253, 6)
tank--cluster-mirror_mlog       (253, 2)
tank--cluster-mirror_mimage_2   (253, 5)
tank--cluster-mirror_mimage_1   (253, 4)
tank--cluster-mirror_mimage_0   (253, 3)
VolGroup00-LogVol01     (253, 1)
VolGroup00-LogVol00     (253, 0)


Expected results:

[root@tank-01 ~]# vgs
  VG           #PV #LV #SN Attr   VSize   VFree  
  VolGroup00     1   2   0 wz--n-  37.16G  64.00M
  tank-cluster   4   1   0 wz--nc 915.70G 615.70G

Additional info:
Comment 1 Jonathan Earl Brassow 2008-03-26 18:17:33 UTC 
The subdevices are logical volumes... but are not generally shown via 'lvs'.  If
you try 'lvs -a', then you will see the underlying logical volumes as well.

I'm not sure why the chose to count the 'non-visible' volumes, but I don't think
their way is wrong either...
Comment 2 Alasdair Kergon 2008-04-10 16:43:43 UTC 
Didn't notice this bz, but hidden LVs should not be included in the totals, so 
it is a bug if that's the output you're still seeing, and it needs fixing.
Comment 3 Alasdair Kergon 2008-04-10 17:18:33 UTC 
fixed in 2.02.34
Comment 4 RHEL Program Management 2008-04-10 17:28:15 UTC 
This request was evaluated by Red Hat Product Management for inclusion in a Red
Hat Enterprise Linux maintenance release.  Product Management has requested
further review of this request by Red Hat Engineering, for potential
inclusion in a Red Hat Enterprise Linux Update release for currently deployed
products.  This request is not yet committed for inclusion in an Update
release.
Comment 7 Corey Marthaler 2008-06-27 19:18:53 UTC 
Fix verified in lvm2-2.02.37-3.el4.
Comment 9 errata-xmlrpc 2008-07-24 20:07:28 UTC 
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on therefore solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHBA-2008-0776.html