Troubleshooting Redundancy

Troubleshooting Connectivity

When the two redundant nodes are connected, the will both appear along with their state details in the Status section of the gateway. There are also various other places where the redundancy state is shown as "connected". If the two nodes cannot connect, check the following:

•	Verify that the master address is correct in the backup. Try to ping the master machine from the backup machine, and verify that you're using the correct address for the network card that the master is connected through.

•	If using system names (or domain names), verify that the name is resolving to the correct address by performing a ping.

•	Verify that the firewall on the master is set to allow TCP traffic to the designated port.

•

Verify that the backup is not connecting and then immediately disconnected for some reason. Viewing the error log in the gateway console section should show this. If errors are occurring at regular intervals, look at the message for an indication of what is happening. An example of a potential problem is when the failover time is set too low for the given network, which results in many socket read timeout exceptions, which in turn leads to many disconnect/reconnect attempts. If errors are occurring, but the cause isn't clear, contact Inductive Automation support.

Advanced Troubleshooting

A variety of loggers can be found under the gateway console section by going to "Levels" and searching for "Redundancy". By setting these loggers to a finer level, more information will be logged to the console. This is generally only useful under the guidance of Inductive Automation support personnel, though more advanced users may find the additional logged information helpful.