Configuring the remote Docker host system on Rational® Test Automation Server

When you are connecting to the remote Docker host system by using host names, you must configure the remote Docker host system on Rational® Test Automation Server before you register the remote Docker host with Rational® Test Automation Server.

Before you begin

You must have set up a remote system installed with Docker Enterprise Edition for a non-secure mode of connection or with Docker Community Edition V18.09 or later, for a secured mode of connection. See Setting up a remote Docker host system or Setting up a secure remote Docker host system.

Procedure

Locate and open the docker-compose.yml file. The file is located in the directory: ibm-rtas/automation/.
Add a configuration called extra_hosts by specifying the Host name and IP address of the remote system under the execution-app service:
```
volumes:
  - ssl_pub:/etc/ssl_pub:ro
  - ./automation/execution:/execution:ro
  - /var/run/docker.sock:/var/run/docker.sock
  - execution_data:/cpsdata
extra_hosts:   
  - "<host>:<ip>"
```
For example, if the Host name is flatrock and the IP address of the remote system is 10.255.204.88, then the added configuration reads as:
```
extra_hosts:
  - "flatrock:10.255.204.88"
```
Note: You can configure the host names and IP addresses of all specific host names of the remote Docker hosts.

If the host name is not being resolved by the DNS of the remote Docker host system, you must provide another DNS server to resolve one or more host names of the remote Docker host system. Go to Step 3.
Add a configuration called dns by specifying the IP address of the remote system, which enables the DNS server to resolve the host names of the remote system, under the execution-app service:
```
volumes:
  - ssl_pub:/etc/ssl_pub:ro
  - ./automation/execution:/execution:ro
  - /var/run/docker.sock:/var/run/docker.sock
  - execution_data:/cpsdata
dns:  
  - <IP address>
```
For example, if the IP address of the remote system is 10.255.204.88, then the added configuration for dns reads as:
```
dns:  
  - 10.255.204.88
```
Restart Rational® Test Automation Server for the changes to take effect.

Results

You have configured the remote Docker host on Rational® Test Automation Server to register the host names of the remote Docker host system.

What to do next

You must register the remote Docker host with Rational® Test Automation Server.