How to configure `auto_activation_volume_list` in lvm.conf file to activate the specific VGs.

Environment

• Red Hat Enterprise Linux 6
• Red Hat Enterprise Linux 7
• Red Hat Enterprise Linux 8
• LVM

Issue

• We have a server with several VGs. We donot want to activate all the VGs automatically at boot time. Out of the following VGs available, only rootvg and datavg needs to be activated automatically.

  VG Name               data_vg
  VG Name               qa_test_vg1
  VG Name               qa_test_vg2
  VG Name               rootvg

Resolution

• Include the VGs that need to be activated at boot in the auto_activation_volume_list parameter in /etc/lvm/lvm.conf file.

• Rebuild initramfs once all the changes are made. This is because the lvm.conf file is present in initramfs as well and hence to keep it updated, intramfs needs to be rebuilt. Please make sure the next reboot is with the newly built initramfs file.

Root Cause

By default /etc/rc.sysinit uses lvchange -a ay (auto-activate all):

if [ -x /sbin/lvm ]; then
        if [ ! -f /.nolvm ] && ! strstr "$cmdline" nolvm ; then
                action $"Setting up Logical Volume Management:" /sbin/lvm vgchange -a ay --sysinit --ignoreskippedcluster  <<====
        else
                echo $"Logical Volume Management disabled at boot."
        fi
fi

The behavior is documented in lvm.conf:

    # By default, the auto_activation_volume_list is not defined and all
    # volumes will be activated either automatically or by using --activate ay/-a ay.

    # auto_activation_volume_list = []                                                   <<== commented, so rc.sysinit will activate 'all' volumes

    # If auto_activation_volume_list is defined and it's not empty, only matching
    # volumes will be activated either automatically or by using --activate ay/-a ay.    

man lvchange

              If autoactivation option is used (-aay), the logical volume is activated only if it matches an item in the activation/auto_activation_volume_list  set  in
              lvm.conf.   If this list is not set, then all volumes are considered for activation. The -aay option should be also used during system boot so it's possi‐
              ble to select which volumes to activate using the activation/auto_activation_volume_list setting.

Example usage to activate only rootvg and data_vg: 

auto_activation_volume_list = [ "rootvg", "data_vg" ] 

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