fix: rely on k3s service readiness instead of installer exit code

The k3s install script can return non-zero while systemd is still bringing the
service up, especially on worker agents. Do not fail immediately on the
installer command; wait for the service to become active and only emit
install diagnostics if the later readiness check fails.

ansible/roles/k3s-agent/tasks/main.yml

@@ -24,30 +24,10 @@
         --node-ip {{ k3s_node_ip }}
         --flannel-iface={{ k3s_flannel_iface }}
         {% if k3s_kubelet_cloud_provider_external | bool %}--kubelet-arg=cloud-provider=external{% endif %}
+      register: k3s_agent_install
+      failed_when: false
       args:
         creates: /usr/local/bin/k3s-agent
-  rescue:
-    - name: Show k3s-agent service status after failed install
-      command: systemctl status k3s-agent --no-pager
-      register: k3s_agent_status_after_install
-      changed_when: false
-      failed_when: false
-
-    - name: Show recent k3s-agent logs after failed install
-      command: journalctl -u k3s-agent -n 120 --no-pager
-      register: k3s_agent_journal_after_install
-      changed_when: false
-      failed_when: false
-
-    - name: Fail with k3s-agent diagnostics
-      fail:
-        msg: |
-          k3s agent install failed on {{ inventory_hostname }}.
-          Service status:
-          {{ k3s_agent_status_after_install.stdout | default('n/a') }}
-
-          Recent logs:
-          {{ k3s_agent_journal_after_install.stdout | default('n/a') }}
 
 - name: Wait for k3s agent to be ready
   command: systemctl is-active k3s-agent
@@ -56,3 +36,34 @@
   retries: 30
   delay: 10
   changed_when: false
+
+- name: Show k3s-agent service status on failure
+  command: systemctl status k3s-agent --no-pager
+  register: k3s_agent_status
+  changed_when: false
+  failed_when: false
+  when: agent_status is failed
+
+- name: Show recent k3s-agent logs on failure
+  command: journalctl -u k3s-agent -n 120 --no-pager
+  register: k3s_agent_journal
+  changed_when: false
+  failed_when: false
+  when: agent_status is failed
+
+- name: Fail with k3s-agent diagnostics
+  fail:
+    msg: |
+      k3s agent failed to become ready on {{ inventory_hostname }}.
+      Install stdout:
+      {{ k3s_agent_install.stdout | default('n/a') }}
+
+      Install stderr:
+      {{ k3s_agent_install.stderr | default('n/a') }}
+
+      Service status:
+      {{ k3s_agent_status.stdout | default('n/a') }}
+
+      Recent logs:
+      {{ k3s_agent_journal.stdout | default('n/a') }}
+  when: agent_status is failed

ansible/roles/k3s-server/tasks/main.yml

@@ -69,6 +69,8 @@
     {% if k3s_disable_embedded_ccm | bool %}--disable-cloud-controller{% endif %}
     {% if k3s_disable_servicelb | bool %}--disable=servicelb{% endif %}
     {% if k3s_kubelet_cloud_provider_external | bool %}--kubelet-arg=cloud-provider=external{% endif %}
+  register: primary_install
+  failed_when: false
   when:
     - k3s_install_needed
     - k3s_primary | default(false)
@@ -92,36 +94,8 @@
         {% if k3s_disable_servicelb | bool %}--disable=servicelb{% endif %}
         {% if k3s_kubelet_cloud_provider_external | bool %}--kubelet-arg=cloud-provider=external{% endif %}
       register: secondary_install
-
-  rescue:
-    - name: Show k3s service status after failed secondary install
-      command: systemctl status k3s --no-pager
-      register: k3s_status_after_install
-      changed_when: false
       failed_when: false
 
-    - name: Show recent k3s logs after failed secondary install
-      command: journalctl -u k3s -n 120 --no-pager
-      register: k3s_journal_after_install
-      changed_when: false
-      failed_when: false
-
-    - name: Fail with secondary install diagnostics
-      fail:
-        msg: |
-          Secondary k3s install failed on {{ inventory_hostname }}.
-          Install stdout:
-          {{ secondary_install.stdout | default('n/a') }}
-
-          Install stderr:
-          {{ secondary_install.stderr | default('n/a') }}
-
-          Service status:
-          {{ k3s_status_after_install.stdout | default('n/a') }}
-
-          Recent logs:
-          {{ k3s_journal_after_install.stdout | default('n/a') }}
-
 - name: Wait for k3s to be ready
   command: "{{ (k3s_primary | default(false)) | ternary('kubectl get nodes', 'systemctl is-active k3s') }}"
   register: k3s_ready