Clustered Volume Group not creating device nodes

General support questions
Post Reply
tokiwinter
Posts: 3
Joined: 2014/07/14 03:05:49

Clustered Volume Group not creating device nodes

Post by tokiwinter » 2014/08/11 01:25:05

Hi all,

I'm following the Red Hat Documentation (https://access.redhat.com/documentation ... -HAAA.html) to enable Exclusive Activation of a Volume Group in a Cluster (by editing the volume_list parameter in /etc/lvm/lvm.conf to exclude the clustered volume groups). However, when I do this and reboot the node, the device nodes are missing under /dev/<vg_name>/<lv_name>. Obviously, this makes creating a filesystem on the logical volumes impossible, and I can't create a clustered LVM resource as the device is not available. If I comment out the volume_list entry in /etc/lvm/lvm.conf and re-run dracut and reboot, the device nodes are visible - but I don't want to risk corrupting my metadata this way (which the Red Hat documentation warns against).

My cluster is quorate and DLM and CLVMD are running:

Code: Select all

# pcs status
Cluster name: webcluster
Last updated: Mon Aug 11 21:19:01 2014
Last change: Mon Aug 11 21:11:18 2014 via cibadmin on centos05
Stack: corosync
Current DC: centos07 (2) - partition with quorum
Version: 1.1.10-32.el7_0-368c726
2 Nodes configured
5 Resources configured


Online: [ centos05 centos07 ]

Full list of resources:

 iscsi-stonith-device	(stonith:fence_scsi):	Started centos05
 Clone Set: dlm-clone [dlm]
     Started: [ centos05 centos07 ]
 Clone Set: clvmd-clone [clvmd]
     Started: [ centos05 centos07 ]

PCSD Status:
  centos05: Online
  centos07: Online

Daemon Status:
  corosync: active/enabled
  pacemaker: active/enabled
  pcsd: active/enabled
When I run an lvscan, the logical volume shows up as inactive:

Code: Select all

[root@centos05 ~]# lvs
  LV        VG      Attr       LSize  Pool Origin Data%  Move Log Cpy%Sync Convert
  root      centos  -wi-ao---- 17.51g
  swap      centos  -wi-ao----  2.00g
  lv_apache vg_data -wi-------  1.00g
[root@centos05 ~]# vgs
  VG      #PV #LV #SN Attr   VSize  VFree
  centos    1   2   0 wz--n- 19.51g    0
  vg_data   1   1   0 wz--nc  7.99g 6.99g
[root@centos05 ~]# ls -ld /dev/vg_data
ls: cannot access /dev/vg_data: No such file or directory
[root@centos05 ~]# lvscan
  inactive          '/dev/vg_data/lv_apache' [1.00 GiB] inherit
  ACTIVE            '/dev/centos/swap' [2.00 GiB] inherit
  ACTIVE            '/dev/centos/root' [17.51 GiB] inherit
I can create an LVM resource using the VG but it remains in a Stopped state:

Code: Select all

[root@centos05 ~]# pcs resource create test_vg LVM volgrpname=vg_data exclusive=true --group=apachegroup
[root@centos05 ~]# pcs resource show
 Clone Set: dlm-clone [dlm]
     Started: [ centos05 centos07 ]
 Clone Set: clvmd-clone [clvmd]
     Started: [ centos05 centos07 ]
 Resource Group: apachegroup
     test_vg	(ocf::heartbeat:LVM):	Stopped
But, a pcs resource debug-start indicates that it cannot activate the volume group:

Code: Select all

[root@centos05 ~]# pcs resource debug-start test_vg
Operation start for test_vg (ocf:heartbeat:LVM) returned 7
 >  stderr: INFO: Activating volume group vg_data
 >  stderr: INFO: Reading all physical volumes. This may take a while... Found volume group "vg_data" using metadata type lvm2 Found volume group "centos" using metadata type lvm2
 >  stderr: INFO: 0 logical volume(s) in volume group "vg_data" now active
 >  stderr: ERROR: LVM Volume vg_data is not available (stopped)
 >  stderr: ERROR: LVM: vg_data did not activate correctly
Does anyone have any ideas as to where the problem may be?

I can supply further information/configuration if required.

Cheers,
Toki

Post Reply