Set up multi-galaxy communication

Multi-Galaxy communication (MGC) lets multiple GR nodes to talk to each other at runtime. MGC is also required for configuring remote GR nodes. To configure multi-galaxy communication, you must configure servers that will perform galaxy service discovery, and then pair the galaxies that will be part of the multi-galaxy.

The functionality of tools such as Object Viewer, Galaxy Browser, ViewApps, and Managed InTouch applications is very similar in a multi-Galaxy environment as it is when working within a single galaxy. However, setting up the multi-galaxy environment requires some basic configuration.

The configuration workflow, using a two-galaxy pair as an example, is as follows:

1. Configure a three node system.

   • IDE node 0 (no GR)

   • GR node 1 (no IDE): contains Galaxy 1

   • GR node 2 (no IDE): contains Galaxy 2

2. Prepare the multi-galaxy environment by adjusting galaxy names as necessary. Each galaxy in a multi-galaxy environment must have a unique name.

3. From the IDE, connect to Galaxy1 on Node1.

4. To configure the service discovery servers for Galaxy 1, select Configure from the Galaxy menu, then select Communication and open the Service discovery servers dialog.

   Set Node 1 as the Primary node for both Local Galaxy servers and the Multi-Galaxy servers. See Defining Service Discovery for additional information about the Local and Multi-Galaxy servers. You can configure secondary nodes for redundancy if needed.

   Important! There can be only one Cross Galaxy Server in a multi-galaxy environment. All GRs in the environment must point to the same Cross Galaxy Server node. You can specify nodes by name or by IP address. However, we recommended that you use the hostname of the node for galaxy pairing.

   If you specify the node by IP address instead of using the node name, make sure the reverse DNS lookup zone is configured properly on the DNS server. If the reverse DNS lookup zone is not set up, galaxy pairing with the node IP address may be successful. However an error message similar to "Failed to get the Discovery Service information for the target Galaxy Repository 'x.x.x.x'" may be generated. You can ignore the error message.

   

5. To configure multi-galaxy communication, select Configure from the Galaxy menu, then select Communication and open the Multi-galaxy configuration dialog.

   1. From the IDE, select the [+] button and add Galaxy 1 (on GR Node 1) as a paired galaxy.

   2. Select the checkbox to enable Remote Pairing. Then, enter a passphrase. The passphrase must be the same for each galaxy to be paired, and must meet a minimum complexity standard:

      • Minimum length is nine characters, including at least eight alphanumeric characters (with at least one upper case and one lower case letter and at least one number)

      • At least one symbol: ! @ # $ % ^ & * ( )

      

   3. Select OK. A message that pairing has been enabled is displayed.

   4. Now, add Galaxy 2 (on GR Node 2) the same way that you added Galaxy 1. The Remote Galaxy Repository Pairing dialog appears.

      

   5. Enter Node 1 as the Target Galaxy Repository, and enter the same Passphrase as you entered for Galaxy 1.

      Node 1 is now listed as a paired Galaxy Repository in the Multi-Galaxy Configuration dialog.

To change the Cross Galaxy Server

Use this procedure to change the Cross Galaxy Server for a previously paired Galaxy:

6. From the IDE, connect to the Galaxy on a remote node.

7. Configure Service Discovery Servers for the Galaxy.

   Set the node as the Local Galaxy Server. Set the new node as the Multi-Galaxy Server. You can configure secondary nodes for redundancy if needed.

   

   When pairing, the GR node initiating the pairing gets a copy of the primary Multi-Galaxy server node if none has been configured.