chcluster Command

Purpose

Changes the cluster configuration.

Syntax

To change the local site cluster topology through addition or deletion of node entities, shared disk entities, or backup repository entities, use the following syntax:
chcluster [ -m [+|-]nodename{[cle_ip=addr1[,cle_ip=addr2][,...],cle_uuid=UUID,cle_globid=id]} [,...] ]
                 [ -d [+|-]shareddisk[,...] ] [ -b [+|-]backupdisk[,...] ] [-n cluster_name ] [-v]
To extend the cluster topology to include a remote site, use the following syntax:
chcluster -S sitename -r remote_reposdisk -m nodename [-s multi_cast_addr] [-n cluster_name ] [-v]
To change the remote site cluster topology through addition or deletion of node entities, use the following syntax:
chcluster -S sitename -m [+|-]nodename [-n cluster_name] [-v]
To change the site cluster topology by adding or removing backup repository entities, use the following syntax:
chcluster  -b [+|-]backupdisk[,...]  [-@ contact_node -S sitename] [-n cluster_name] [-v]
To change the attribute on a site entity, use the following syntax:
chcluster -S sitename{[cle_name=new_name,cle_prio=prio]}
To change the attribute of a node entity, use the following syntax:
chcluster -m nodename{[[+|-]cle_ip=addr1[,cle_ip=addr2][,...] | cle_hostname=name]} [ -S sitename ] [-v]

Description

The chcluster command changes the cluster configuration.

The chcluster command adds and removes the storage area network (SAN) shared disks and nodes to or from the cluster configuration, or extends the existing cluster to span multiple sites. When you create another site, specify only one remote node, along with the remote site name, remote repository disk name, and the remote site multicast address (optional). Additional remote nodes can be added after the remote site is created.

Flags

Item Description
-@ at_node Specifies the node where the disk universal unique identifier (UUID) is located. The node must be reachable and within the same site that the disk is located. It is optional for local site changes but required for remote site changes. This flag applies only to the disks that are specified by the -b flag.
-b [+|-] backupdisk [,...] Specifies a comma-separated list of SAN shared storage device such as hdisk5, hdisk6. These disks are used as the backup for the central repository of the cluster. When the central repository is inaccessible, the disk from the list is used as a replacement. These devices must be accessible from all nodes in the site.
-d [+|-] shareddisk [,....] Specifies a comma-separated list of shared storage device names to be added to or removed from the cluster configuration. The shared disks must not be open when the chcluster command is run. The disk must be in the local site of the node that is running the command.
-m [+|-]node[,...] Specifies a comma-separated list of node names to be added to or removed from the cluster configuration.
The following node information can be specified only when a node is added to the cluster:
cle_uuid
Specifies the node UUID that is used if the note is unique across the cluster. If the node UUID is not specified, it is automatically generated.
cle_globid
Specifies the short ID of the node that must be a unique unsigned number. The value must be greater than zero. If the short ID is not specified, it is automatically generated.
The following node attributes can be specified with any arguments:
cle_ip

Specifies the gateway address of the node (in case the cluster spans across multiple sites). Typically, this attribute is the address through which the node can be reached from an external node. This attribute can be specified in either an IPv4 or IPv6 format.

If a new node is added to the cluster by specifying the + sign and additional values, the node is added to the cluster with the specified values.

If an existing node is specified with the + sign and additional attributes, the new attributes are added to the node.

If an existing node is specified with the - sign and additional attributes, the specified attributes are deleted from the node.

cle_hostname

Specifies the new host name of the node.

-n name Specifies the name of the cluster that needs to be changed. If this flag is omitted, the default cluster is used.
-v Specifies verbose mode.
-r +remote_reposdisk Specifies the name of the remote disk that is used as the repository of the remote site, as seen on the first remote node. This flag is used only for remote site creation.
-s +multi_cast_addr Specifies the multicast address that is used for the remote site. If this flag is omitted, a default multicast address is generated.
-S +sitename Specifies the name of the site that is associated with the specified entities. Currently, a cluster supports only 2 sites. If this flag is omitted, the site of the running node is used.
The following site information can be specified only during site creation:
cle_uuid
Specifies the site UUID that is used if the node is unique across the cluster. If the site UUID is not specified, it is automatically generated.
cle_globid
The short ID of the site that must be a unique unsigned number. The value must be greater than zero. If short ID is not specified, it is automatically generated.
The following site attribute can be specified during site creation:
cle_prio
Specifies the priority of a site. A lower value indicates a higher priority. The priority is mainly used in the context of synchronizing the repository metadata. If two sites split and the repository data becomes out-of-sync, the data from the site with higher priority is copied over to the site with lower priority.
If a site already exists, the following attributes can be changed:
cle_name
Specifies the new name of the site.
cle_prio
Specifies the new priority of the site.
The other values cannot be changed.

Examples

  1. To add shared disks to the cluster configuration:
    chcluster -n mycluster -d +hdisk20,+hdisk21
  2. To remove shared disks from the cluster configuration:
     chcluster -n mycluster -d -hdisk20,-hdisk21
  3. To add nodes to the cluster configuration:
    chcluster -n mycluster -m +nodeD,+nodeE
  4. To remove nodes from the cluster configuration:
    chcluster -n mycluster -m -nodeD,-nodeE
  5. To add a site to the cluster configuration:
    chcluster -n mycluster -S +remotesite -m +nodeZ -r +hdisk5
    where hdisk5 is the name of the disk as seen by nodeZ node.
  6. To change the name of an existing site:
    chcluster -n mycluster -S remotesite{cle_name=myremotesite}
    
  7. To change the name of an existing node in the cluster:
    chcluster -n dynamicCluster –m rosy{cle_hostname=pinky}
  8. To add the backup disks hdisk1 and hdisk2 to the local site, enter the following command:
    chcluster -S Local -b +hdisk1,+hdisk2
  9. To remove the backup disks hdisk1 and hdisk2 from the local site, enter the following command:
    chcluster -S Local -b -hdisk1,-hdisk2
  10. To add the backup disks hdisk3 and hdisk4 to the remote site, enter the following command:
    chcluster -S Remote -b +hdisk3,+hdisk4 -@ remote_node
  11. To remove the backup disks hdisk3 and hdisk4 from the remote site, enter the following command:
    chcluster -S Remote -b -hdisk3,-hdisk4 -@ remote_node