Skip to navigation

How do I change a clustered LVM volume group to non-clustered on Red Hat Enterprise Linux?

Updated 2014-04-14T12:54:09+00:00

Issue

  • How do I change a volume group to clustered or non-clustered?
  • We need to mount the Clone LUN's onto another RHEL server so that we can write the data to tape from that server. While mounting the VG's on the RHEL server, I am getting the below error:
# vgimport /dev/mapper/mpath0 
  connect() failed on local socket: Connection refused 
  WARNING: Falling back to local file-based locking. 
  Volume Groups with the clustered attribute will be inaccessible. 
  Skipping clustered volume group vgname
  • How to convert a volume group from clustered to non-clustered and vice-versa?

Environment

  • Red Hat Enterprise Linux (RHEL) including
    • Red Hat Enterprise Linux 4
    • Red Hat Enterprise Linux 5
    • Red Hat Enterprise Linux 6
  • May or may not require Red Hat High Availability Cluster
  • LVM2 volume management

    • The volume group is clustered:

      • There are 2 ways to determine; firstly using vgdisplay:
      # vgdisplay vgtest --config 'global {locking_type = 0}' | grep Clustered
        WARNING: Locking disabled. Be careful! This could corrupt your metadata.
        Clustered             yes
      
      • Also, vgs will display the 'c' attribute for clustered volume groups:
      # vgs --config 'global {locking_type = 0}'
        WARNING: Locking disabled. Be careful! This could corrupt your metadata.
        VG     #PV #LV #SN Attr   VSize  VFree 
        vgname   1   1   0 wz--nc 96.00M 76.00M       <----- Attr includes the 'c' flag meaning clustered.
      
    • It is undesirable that the volume group is clustered. Possible reasons include:

      • The volume group is being converted to non-clustered permanently.
      • The command vgchange -cy was accidentally run on the volume group or the volume group was accidentally made clusrered.
        • The cluster cannot form quorum, or clvmd cannot start and the volume group needs to be temporarily un-clustered to restore service.

Subscriber content preview. For full access to the Red Hat Knowledgebase, please log in.

Not a subscriber? Learn more about the benefits of Red Hat Subscriptions.