Instead of upgrading a running instance when a new version of the software is released, we recommend the following:
- Start an instance of the newer software,
- Migrate the configuration over from the old one,
- Terminate the old instance.
Note: When the cluster is in a mixed state (i.e. the traffic managers are using different software versions) do not make any configuration changes. This should remain the case until all traffic manager instances in the cluster are running the upgraded version.
For each traffic manager in your cluster, perform the following steps:
Start an instance of the new AMI.
- Using the Admin Server, or the user-data pre-configuration parameters, join the new instance to your cluster.
- If using user-data pre-configuration, you can set the new instance to join the Traffic IP Groups by setting join_tips=y but do not use this option if there are multiple Traffic IP groups configured in the cluster. Also for Amazon VPC instances, it will be ignored if the instance doesn't have a secondary IP address assigned whilst launching. Note that per-node hostname mappings (configured the in System > Networking page) will not be migrated automatically - you must set these manually on each new instance
- Terminate one of the old instances in your cluster.
Repeat these steps until all the traffic managers in your cluster have been replaced. Replace instances one by one - do not terminate an old instance until its replacement has successfully joined the cluster.
For more information, please see the attached document - Upgrading Stingray Traffic Manager on Amazon EC2.