Loopback alias configuration

Expecting an appserver to run when the machine is disconnected from the network requires that the loopback port address (127.0.0.1) is configured as an alias endpoint for the machine. The reason for this is that the Node Agent normally pings all application servers on the node. When the Node Agent detects that an application server is not available, it stops and tries to restart the application server. This goes on for 10 minutes, at which time the Node Agent no longer tries to restart the application server. The ping from the Node Agent to the application server uses the Internet Protocol (IP). If the machine is disconnected from the network, the communication occurs on the loopback port. However, the loopback port is only considered a valid port for the application server when the loopback port address (127.0.0.1) is configured as an alias for the machine.

The behavior when the loopback port is not configured as an alias is that the appserver is stopped (because the Node Agent cannot reach the application server), and the Node Agent will not be able to restart it until the machine is again connected to the network. If the time required to reconnect to the network is less than 10 minutes, then the application servers will be started on the next retry of the Node Agent. However, when the reconnection time exceeds the 10-minute interval, then an explicit start of the application servers has to be performed.

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