refactor ♻️: Refactor task to extract and process Corosync ring addresses, determine their CIDRs, and update ignoreip in fail2ban config

This refactoring extracts the logic for processing Corosync ring addresses and determining their CIDRs. It then updates the `ignoreip` setting in the fail2ban configuration accordingly. This change improves modularity and maintainability of the code.

tasks/fail2ban.yml

@@ -21,9 +21,8 @@
 #################################################
 
 - name: fail2ban | Get Proxmox node name
-  ansible.builtin.command: hostname
-  register: pve_node
-  changed_when: false
+  ansible.builtin.set_fact:
+    pve_node: "{{ ansible_hostname }}"
 
 - name: fail2ban | Set firewall config path
   ansible.builtin.set_fact:
@@ -89,7 +88,7 @@
   ansible.builtin.command: pve-firewall compile
   register: compiled_fw
   changed_when: false
-  failed_when: false
+  failed_when: fw_compile_check.rc != 0
   when: cluster_status.stat.exists
 
 - name: fail2ban | Fail if corosync ports are being dropped
@@ -140,15 +139,33 @@
   notify: Reload pve firewall
   # noqa risky-file-permissions
 
-- name: fail2ban | Extract corosync ring0 address
+- name: fail2ban | Extract all corosync ring addresses
   ansible.builtin.shell: |
     set -o pipefail
-    grep ring0_addr /etc/pve/corosync.conf | awk '{print $2}'
+    awk '/ring[0-9]+_addr/ {print $2}' /etc/pve/corosync.conf
   args:
     executable: /bin/bash
-  register: corosync_ip
+  register: corosync_ips
   changed_when: false
-  when: cluster_status.stat.exists
+  when: pve_clustered
+
+- name: fail2ban | Determine CIDR for each corosync IP
+  ansible.builtin.command: ip route get {{ item }}
+  register: corosync_routes
+  changed_when: false
+  loop: "{{ corosync_ips.stdout_lines }}"
+  when: pve_clustered
+
+- name: fail2ban | Extract network CIDRs
+  ansible.builtin.set_fact:
+    corosync_networks: >-
+      {{
+        corosync_routes.results
+        | map(attribute='stdout')
+        | map('regex_search', 'src ([0-9.]+)/([0-9]+)', '\\1/\\2')
+        | list
+      }}
+  when: pve_clustered
 
 - name: fail2ban | Validate Proxmox firewall configuration
   ansible.builtin.command: pve-firewall compile
@@ -200,7 +217,7 @@
       bantime.max = {{ f2b_bantime_max }}
       backend  = systemd
       banaction = proxmox-fw
-      ignoreip = 127.0.0.1/8{% if pve_clustered %} {{ corosync_ip.stdout }}{% endif %} 192.168.2.0/24
+      ignoreip = 127.0.0.1/8{% if pve_clustered %} {{ corosync_networks | join(' ') }}{% endif %} 192.168.2.0/24
 
       #################################################
       # SSH