DNS

If the Active host on which the Broker is running fails and cannot be restarted, edit the /etc/hosts file so that the DNS of the Active host that has failed, points to the IP address of the Standby host. The Failover Manager will recognize the DNS of the failed host and identify the IP address of the Standby host as running and start the Broker on the Standby host. The Failover Manager then synchronizes all the Active SAM and Domain Managers to the Broker.

The /etc/hosts file of each server (host) must be edited to avoid a downtime in Broker communication. You must ensure that any cache in the DNS is cleared so that all SAM and Domain Managers point to the Standby host.

Example:

An example of a /etc/hosts file is provided below:

In the example, the left column is the IP address of the Active host. The next column is the DNS of the host. Any subsequent columns are aliases for that host.

# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1 localhost.localdomain localhost
::1 localhost6.localdomain6 localhost6
xx.x.xx.230 itops-tco-230.lss.emc.com itops-tco-230
xx.x.xx.227 itops-tco-227.lss.emc.com itops-tco-227

If the Broker running at itops-tco-227.lss.emc.com fails, edit the etc/hosts file as shown below:

# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1 localhost.localdomain localhost
::1 localhost6.localdomain6 localhost6
xx.x.xx.230 itops-tco-230.lss.emc.com itops-tco-230
xx.x.xx.228 itops-tco-227.lss.emc.com itops-tco-227

After making the configuration changes, you must restart your network for the changes to take effect. Type the following command to restart your network:

/etc/rc.d/init.d/network restart

The following messages are displayed:

Shutting down interface eth0: [ OK ]
Shutting down loopback interface: [ OK ]
Bringing up loopback interface: [ OK ]
Bringing up interface eth0: [ OK ]