sap_swpm: Add support for HA virtual hostname resolution

Signed-off-by: Bernd Finger <[email protected]>

roles/sap_swpm/README.md

@@ -414,7 +414,9 @@ Define DDIC user password in client 000 for new install, or existing for restore
 - _Type:_ `string`
 
 Define virtual hostname when installing High Available instances (e.g. SAP ASCS/ERS cluster).
-
+The role attempts to resolve `sap_swpm_virtual_hostname` on the managed node, using DNS and /etc/hosts, and will fail
+if this hostname resolution fails. The role will also fail if the IPv4 address for `sap_swpm_virtual_hostname` is
+not part of the IPv4 addresses of the managed node.
 
 ### Variables specific to SAP HANA Database Installation
 
@@ -856,4 +858,4 @@ Set owner for all non-SAPCAR files in `sap_swpm_software_path` and for SWPM*.SAR
 - _Default:_ `root`
 
 Set group ownership for all non-SAPCAR files in `sap_swpm_software_path` and for SWPM*.SAR files in `sap_swpm_swpm_path`.
-<!-- END Role Variables -->
+<!-- END Role Variables -->

roles/sap_swpm/defaults/main.yml

@@ -241,7 +241,7 @@ sap_swpm_ddic_000_password:
 
 # initial = not an HA setup
 # set this in the input file when installing ascs, ers to indicate an HA setup
-sap_swpm_virtual_hostname: "initial"
+sap_swpm_virtual_hostname:
 
 
 ########################################

roles/sap_swpm/tasks/pre_install.yml

@@ -147,6 +147,18 @@
 
 # /etc/hosts
 
+- name: SAP SWPM Pre Install - Assert hostname resolution for HA
+  ansible.builtin.include_tasks:
+    file: pre_install/assert_hostname_resolution_for_ha.yml
+    apply:
+      tags: sap_swpm_update_etchosts
+  when:
+    - sap_swpm_run_sapinst
+    - sap_swpm_update_etchosts
+    - sap_swpm_virtual_hostname | type_debug != 'NoneType'
+    - sap_swpm_virtual_hostname | length > 0
+  tags: sap_swpm_update_etchosts
+
 - name: SAP SWPM Pre Install - Update /etc/hosts
   ansible.builtin.include_tasks:
     file: pre_install/update_etchosts.yml

roles/sap_swpm/tasks/pre_install/assert_hostname_resolution_for_ha.yml

@@ -0,0 +1,48 @@
+# SPDX-License-Identifier: Apache-2.0
+---
+
+# Assert HA settings
+
+- name: SAP SWPM Pre Install - HA settings - Ensure the dig command is present
+  ansible.builtin.package:
+    name: bind-utils
+    state: present
+
+- name: SAP SWPM Pre Install - HA settings - Try to resolve sap_swpm_virtual_hostname from DNS
+  ansible.builtin.command: dig +short +tries=1 +time=1 "{{ sap_swpm_virtual_hostname }}"
+  register: __sap_swpm_register_virtual_ip_dns
+  changed_when: false
+  failed_when: false
+
+- name: SAP SWPM Pre Install - HA settings - Assign sap_swpm_virtual_ip from DNS
+  ansible.builtin.set_fact:
+    __sap_swpm_fact_virtual_ip: "{{ __sap_swpm_register_virtual_ip_dns.stdout_lines[-1] }}"
+  when: __sap_swpm_register_virtual_ip_dns.stdout_lines | length > 0
+
+- name: SAP SWPM Pre Install - HA settings - Try using /etc/hosts for name resolution
+  when: __sap_swpm_register_virtual_ip_dns.stdout_lines | length == 0
+  block:
+
+    - name: SAP SWPM Pre Install - HA settings - Try to resolve sap_swpm_virtual_hostname from /etc/hosts
+      ansible.builtin.shell: |
+        awk '/\s{{ sap_swpm_virtual_hostname }}\./||/\s{{ sap_swpm_virtual_hostname }}/{print $1}' /etc/hosts
+      register: __sap_swpm_register_virtual_ip_etc_hosts
+      changed_when: false
+      failed_when: false
+
+    - name: SAP SWPM Pre Install - HA settings - Assign sap_swpm_virtual_ip from /etc/hosts
+      ansible.builtin.set_fact:
+        __sap_swpm_fact_virtual_ip: "{{ __sap_swpm_register_virtual_ip_etc_hosts.stdout_lines[-1] }}"
+      when: __sap_swpm_register_virtual_ip_etc_hosts.stdout_lines | length > 0
+
+- name: SAP SWPM Pre Install - HA settings - Assert that sap_swpm_virtual_hostname can be resolved
+  ansible.builtin.assert:
+    that: __sap_swpm_fact_virtual_ip | length > 0
+    fail_msg: "FAIL: sap_swpm_virtual_hostname cannot be resolved!"
+    success_msg: "PASS: sap_swpm__virtual_hostname can be resolved."
+
+- name: SAP SWPM Pre Install - HA settings - Assert that sap_swpm_fact_virtual_ip is part of ansible_all_ipv4_addresses
+  ansible.builtin.assert:
+    that: __sap_swpm_fact_virtual_ip in ansible_all_ipv4_addresses
+    fail_msg: "FAIL: __sap_swpm_fact_virtual_ip is not part of ansible_all_ipv4_addresses!"
+    success_msg: "PASS: __sap_swpm_fact_virtual_ip is part of ansible_all_ipv4_addresses."