Overcloud instance HA deployment fails with "Stonith" error in RHOSP10.

Issue

• Unable to configure overcloud instance HA in RHOSP10.

• While following the instanceHA configuration guide we see the below error occurs when running the playbook to configure overcloud instance HA on our production environment:

TASK [stonith-config : Generate STONITH script] ********************************************************************************************************************************************************************
fatal: [imrhodn001]: FAILED! => {"changed": true, "cmd": "source /home/stack/stackrc\n /home/stack/config_stonith_from_instackenv.py /home/stack/instackenv.json install controllers", "delta": "0:00:01.385331", "end": "2018-11-19 13:56:21.859755", "msg": "non-zero return code", "rc": 1, "start": "2018-11-19 13:56:20.474424", "stderr": "Traceback (most recent call last):\n  File \"/home/stack/config_stonith_from_instackenv.py\", line 73, in <module>\n    if (node[\"mac\"][0].lower() == instance.addresses['ctlplane'][0]['OS-EXT-IPS-MAC:mac_addr']\nKeyError: 'mac'", "stderr_lines": ["Traceback (most recent call last):", "  File \"/home/stack/config_stonith_from_instackenv.py\", line 73, in <module>", "    if (node[\"mac\"][0].lower() == instance.addresses['ctlplane'][0]['OS-EXT-IPS-MAC:mac_addr']", "KeyError: 'mac'"], "stdout": "pcs property set stonith-enabled=true", "stdout_lines": ["pcs property set stonith-enabled=true"]}
        to retry, use: --limit @/home/stack/tripleo-ha-utils/playbooks/overcloud-instance-ha.retry

PLAY RECAP *********************************************************************************************************************************************************************************************************

• What is causing these errors to occur and the deployment to fail?