Configuring CES protocol service IP addresses

Protocol services are made available through Cluster Export Services (CES) protocol service IP addresses. These addresses are separate from the IP addresses that are used internally by the cluster.

Each CES protocol service IP address is assigned initially to one CES node, either explicitly as specified by the mmces address add command, or by the system, but they can be moved later either manually or automatically in response to certain events.

mmces address add --ces-node Node1 --ces-ip 192.168.6.6

After adding all desired CES protocol service IP addresses, verify the configuration:

mmces address list

Use mmces address add --ces-ip 192.168.6.6 to add an IP address to the CES IP address pool. The IP address will be assigned to a CES node according to the CES "Address distribution policy".

CES addresses can be assigned to CES groups. A CES group is identified by a group name consisting of alphanumeric characters which are case-sensitive. Addresses can be assigned to a group when they are defined by issuing the following command:

mmces address add --ces-ip 192.168.6.6 --ces-group group1

The group assignment can be changed by issuing the following command:

mmces address change --ces-ip 192.168.6.6 --ces-group group2

The group assignment can be removed by issuing the following command:

mmces address change --ces-ip 192.168.6.6 --remove-group

A CES address that is associated with a group must be assigned only to a node that is also associated with the same group. A node can belong to multiple groups while an address cannot.

As an example, consider a configuration with three nodes. All three nodes can host addresses on subnet A, and two of the nodes can host addresses on subnet B. The nodes must have existing non-CES IP address of the same subnet configured on the interfaces intended to be used for the CES IPs. Also four addresses are defined, two on each subnet.

Node1: groups=subnetA,subnetB

Node2: groups=subnetA,subnetB

Node3: groups=subnetA

Address1: subnetA

Address2: subnetA

Address3: subnetB

Address4: subnetB

In this example, Address1 and Address2 can be assigned to any of the three nodes, but Address3 and Address4 can be assigned to only Node1 or Node2.

If an address is assigned to a group for which there are no healthy nodes, the address will remain unassigned until a node in the same group becomes available.

Addresses without a group assignment can be assigned to any node. Therefore, it is necessary to use a group for each subnet when multiple subnets exist.

Note: IP addresses that are assigned attributes (such as object_database_node or object_singleton_node) do not follow the same policy rules that other IP addresses follow. If a node has an affinity policy set, the IP address that is associated with the assigned attribute fails back to its node.

For more information, see mmces command.