The following describes methods to change over to a cluster system from one or more single nodes where classes have already existed by installing the cluster control facility. The procedure varies depending on each class type.
Root class
Unmirror the system disk, then install and set up the initial configuration of the cluster control facility. After that, set up the mirror of the system disk.
Local class
Back up the volume data as necessary, and then delete the local class. Install and set up the initial configuration of the cluster control facility, and then create the classes and volumes again. Restore the backed up volume data as necessary.
Important Point 1
A root or local class created on a single node cannot be used directly in a cluster system. For local classes, when the cluster control facility is activated, the following error message is output to the system log and the GDS daemon log file, and the operation of the local class becomes unavailable.
ERROR: class: cannot operate in cluster environment, created when cluster control facility not ready
For details on resolution, see "The error message "(1) The error message "ERROR: class: cannot operate in cluster environment, ..." is output, and the operation cannot be conducted on the class class." in "D.1.10 Cluster System Related Error."
Important Point 2
Expanding the class scope after changing over from multiple single nodes to a cluster system, may output the following messages.
ERROR: class: class names must be unique within a domain
This error occurs when the name of a class created on a single node is the duplicate name of a class on another node. If this error occurs, rename either of the classes, and expand the class scope.
ERROR: class: volume minor numbers must be unique within a domain
This error occurs when the minor number of a volume created on a single node is the duplicate number of a volume on another node. If this error occurs, re-create either of the volumes, and expand the class scope.
The minor number of a volume can be viewed in the following manner.
# cd /dev/sfdsk/class/dsk # ls -l |
Additionally, this error may occur when any lower level group exists in a class created on a single node or a class on another node. In this event, duplicate miner numbers cannot be checked with the method as shown above. Re-create all volumes and lower level groups in the class created on the single node and then expand the class scope.
