primary node

In clustered environments, probes are installed on all nodes, and each probe is configured as though that node is the primary node.

There can be up to 7 servers in a cluster, and any node can be the primary node.

This is usually easiest by focusing on the primary node of a domain.

In the case of an e-commerce system, the primary node could be either an order or a customer.

Migration is simply a failover that never fails back, and scaling up is a failover in which the primary node never goes offline.

In the example environment, running lspv on the primary node confirms the shared volume group is in concurrent mode.

Scaling down is like a failback operation without the task of bringing the primary node up.

Write operations occur through the primary node and are performed to the local storage and secondary storage simultaneously (see Figure 3).

All writes are directed to the primary node, from where they are replicated while reads can be performed on any node.

The reason is that the copy on the secondary node is still pointing to the repository of the primary node.

The secondary node is promoted to primary if the clustering solution detects that the primary node is down.

The primary node has ownership of the shared volume group as it is varied-on and active.

All probes will be active, but only the primary node will forward monitored transactions.

The middle column should be the hostname of the primary node.

Change the hostname of the secondary node to the primary node's hostname.

The complementary action is to failback when the primary node is recovered.

Selecting the primary option installs a primary node and creates a cluster.

Upon failure of the primary node the redundant node takes over.

Use the ps command to make sure the Web server daemons are running on the primary node.

The DB2 database installed with the primary node is automatically used by all other nodes in the cluster.

Note that I am using the cluster address in the above URLs and not the address of the primary node.

Command to make sure WebSphere MQ is running on the primary node.

Every node has one and only one primary node type.

Allow the secondary node to access objects backed up on the primary node (this has to be done on the primary machine)

On the primary node (ha1) create a highly available queue manager using the command shown below (as root)

Create the DB2 users and groups on the primary node (Node1) and enter

Installing DB2 on the primary node