Changing hostname

You can set custom hostname for control nodes on Cloud Pak for Data System. If NPS is installed, additional steps might be required.

1. Connect to mgmt1 IP of e1n1.
2. For management network IPs, update the IP values or custom hostnames, or both by following Node specific information.
3. Validate the YAML file.
4. Test the YAML file and run the playbooks.
5. Validate that all nodes are accessible through their management IP addresses (nodes 1 - 3 and floating_ip).
6. If you have NPS installed and the Cloud Pak for Data System version is 1.x, follow these steps to reflect the change on NPS containers:
   1. Upgrade the container, following the steps as described in Upgrading the NPS container. The upgrade must be done to the same version as the one currently installed. By doing so, you ensure that the changes are applied to all control nodes. To check the current container version, run:

      docker inspect ipshost1 | grep -i version

   2. After the container upgrade is completed, do not start NPS. Keep NPS in the Stopped state.
   3. Redeploy the container on other nodes as described in Redeploying the container
   4. When finished, start NPS: as the nz user, inside the container, run nzstart.

   Draft comment: anna.bogusz@pl.ibm.com
   On Cloud Pak for Data System version 2.x no additional steps are required as the pod with NPS host runs on a worker node.

   Note: After changing the hostnames the NPS container will rely on the external DNS server to resolve the names of bare metal hosts. If you are using NPS, new hostnames have to be resolvable by external DNS. If this condition is not met the NPS will fail to start with message ERROR: There should be exactly one ip address found for <new hostname>.