Zeus Traffic Manager ServerTemplates

Security Group Settings

The following ports should be allowed in the Security Groups for your Traffic Managers:

• For system administration, TCP ports 22 (SSH command-line access) and 9090 (management port for the web-based Admin UI) should be open to connections from your network gateway;
• TCP port 80 (and any other ports required for your configured services) should be open to the world;
• TCP ports 9080 and 9090, and UDP ports 9080 and 9090, should be open between Traffic Manager nodes in your Deployment.

Set up your first Traffic Manager

Zeus Traffic Manager is designed to work best as multiple instances together in a clustered arrangement, in order to provide greater capacity and fault tolerance. It can, however, work as a stand-alone instance.

• For a single Traffic Manager, set the OPT_CLUSTER_HOST and OPT_CLUSTER_PORT inputs to "ignore" as there is no cluster to join. Subsequent Traffic Managers may set these to the hostname and port of the Traffic Manager they wish to cluster with.
• The ZEUS_ADMIN_PASSWORD input should be set in all cases. This is the ‘admin’ user password used to log into the Traffic Manager to configure it. This password will also be used by additional Traffic Managers wishing to join the cluster, and by backend web servers wishing to join server pools.
• Once a Traffic Manager is operational, you can log into the web-based Admin UI and configure it. Set your browser URL to the hostname or IP address of the new Traffic Manager, on port 9090. You should be presented with the Admin UI login screen.

Add a Traffic Manager to a cluster

A cluster of Zeus Traffic Managers is created by first launching a single Traffic Manager instance, then launching additional Traffic Managers and instructing them to cluster with the first.

• Once the first Traffic Manager instance is running, you can launch subsequent instances and instruct them to cluster with the first.
• Set the OPT_CLUSTER_HOST and OPT_CLUSTER_PORT inputs to the hostname and management port of another Traffic Manager in the cluster you want to join. It is not necessary to always specify the same Traffic Manager, as once they are clustered each Traffic Manager becomes capable of accepting cluster requests from new instances.
• OPT_CLUSTER_PORT defaults to 9090. ZEUS_ADMIN_PASSWORD should be set to the ‘admin’ user password of the machine with which you wish to cluster.
• You can create an auto-scaling array of Traffic Managers, using the performance statistics reported by each machine to drive scaling up and scaling down.

Remove a Traffic Manager from a cluster

A Traffic Manager will automatically remove itself from a cluster when it is shut down. The remaining Traffic Managers will automatically recognize the removal of the node and adjust their configuration accordingly.

Add and Remove backend servers

You can configure your backend web servers to add themselves to the Traffic Manager's load-balanced server pools automatically.

• Import the Zeus backend connect script from the MultiCloud Marketplace into your account's local collection. Add it to your web backend ServerTemplates as a Boot script. This will cause a server based on this template to be automatically added into the desired server pool when it is started up.
  • Set the LB_HOSTNAME input to be the hostname or IP address of a traffic manager in your cluster.
  • Set the LB_APPLISTENER_NAME input to the name of the server pool which you wish to join.
• Import the "Zeus backend disconnect" script from the MultiCloud Marketplace into your 'Local' collection. Add it to your web backend ServerTemplates as a Decommission Script to ensure that a server based on this ServerTemplate will automatically and cleanly remove itself from the Traffic Manager cluster configuration when it's shuts down. (Note: You may need to clone the ServerTemplate to create an editable version.)
  • Set the LB_HOSTNAME input to be the hostname or IP address of a Traffic Manager in your cluster.
  • Set the LB_APPLISTENER_NAME input to the name of the server pool of which the backend is a member.
• You can create an auto-scaling array of backend servers, using the performance statistics reported by the Traffic Manager cluster and the backend servers themselves to drive scaling up and scaling down.

Upgrading a traffic manager

The RightScale environment enables an administrator to start and stop new instances of the traffic manager to suit the needs of the services being provided.  Instead of upgrading a running traffic manager instance when a new version of the software is released, it is simpler and less disruptive to start an instance of the newer software, migrate the configuration over from the old one, and then terminate the old instance.  The following steps can be performed for each traffic manager in your cluster:

• Start an instance of the new ServerTemplate version.

• Using the Admin UI, or the OPT_CLUSTER_HOST input for the “Zeus Traffic Manager configure” RightScript, join the new instance to your cluster.  Ensure that you set the new instance to join the appropriate Traffic IP groups.  Note that per-node hostname mappings (configured on the System > Networking page of the Admin UI) 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.