If upgrading to Java 9, the
ignition.conf file needs to be modified to comment out a specific parameter:
CMSPermGenSweepingEnabled which is located under the Additional Parameters section. If the line is not commented out, then the Gateway will be unable to start.
This can be accomplished by placing a
# character in front of the line, or by removing the line entirely, saving the file, and starting the service.
Note that as of Ignition version 7.9.6+, Java 9 is now officially supported. As a result, the
CMSPermGenSweepingEnabled parameter will automatically be commented out by upgrading to Ignition 7.9.6 or greater when using Java 9.
Java 9 is the maximum version allowed.