Red Hat SummitF.3. Creating New Logical Volumes for an Existing Cluster
To create new volumes, either volumes need to be added to a managed volume group on the node where it is already activated by the service, or the
volume_list must be temporarily bypassed or overridden to allow for creation of the volumes until they can be prepared to be configured by a cluster resource.
Note
New logical volumes can be added only to existing volume groups managed by a cluster
lvm resource if lv_name is not specified. The lvm resource agent allows for only a single logical volume within a volume group if that resource is managing volumes individually, rather than at a volume group level.
To create a new logical volume when the service containing the volume group where the new volumes will live is already active, use the following procedure.
- The volume group should already be tagged on the node owning that service, so simply create the volumes with a standard
lvcreatecommand on that node.Determine the current owner of the relevant service.#
clustatOn the node where the service is started, create the logical volume.#
lvcreate -l 100%FREE -n lv2 myVG - Add the volume into the service configuration in whatever way is necessary.
To create a new volume group entirely, use the following procedure.
- Create the volume group on one node using that node's name as a tag, which should be included in the
volume_list. Specify any desired settings for this volume group as normal and specify--addtagnodename, as in the following example:#
vgcreate myNewVG /dev/mapper/mpathb --addtag node1.example.com - Create volumes within this volume group as normal, otherwise perform any necessary administration on the volume group.
- When the volume group activity is complete, deactivate the volume group and remove the tag.
#
vgchange -an myNewVg --deltag node1.example.com - Add the volume into the service configuration in whatever way is necessary.
