Merge pull request #1084 from infinito-nexus/fix/svc-storage-nfs-client/ganesha-dir-delegation

fix(svc-storage-nfs-client): stop requesting directory delegations from ganesha < 9.11

roles/svc-storage-nfs-client/README.md

@@ -50,6 +50,12 @@ Solid `1:1` edges are fixed relationships; dashed `0..1` edges are conditional (
   Generations written to the share before the bind stay under the
   export's `backup/` directory, hidden from the nodes; remove them there
   by hand.
+- **Directory delegations off against old ganesha:** When the server
+  runs nfs-ganesha older than 9.11, every client and the controller set
+  the kernel's `nfsv4` parameter `directory_delegations` to `N`, at
+  runtime and in `/etc/modprobe.d`. The parameter is kernel-wide, so on
+  a lab whose nodes share one kernel it covers every NFS mount of that
+  host until the module reloads.
 
 ## Quick Setup
 

roles/svc-storage-nfs-client/files/shell/directory_delegations.sh

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+set -eu
+param=/sys/module/nfsv4/parameters/directory_delegations
+
+[ -e "${param}" ] || exit 0
+[ "$(cat "${param}")" = N ] && exit 0
+echo N >"${param}"
+echo CHANGED

roles/svc-storage-nfs-client/tasks/directory_delegations.yml

@@ -0,0 +1,27 @@
+---
+- name: "🔍 Read the NFS server's installed packages"
+  ansible.builtin.package_facts:
+  delegate_to: "{{ groups['svc-storage-nfs-server'] | first }}"
+  delegate_facts: true
+  run_once: true
+
+- name: "🔧 Stop requesting directory delegations from a ganesha that rejects them"
+  when: >-
+    (hostvars[groups['svc-storage-nfs-server'] | first].ansible_facts.packages['nfs-ganesha'] | first).version
+    is version('9.11', '<')
+  block:
+    - name: "🔧 Keep directory delegations off whenever nfsv4 loads"
+      ansible.builtin.lineinfile:
+        path: /etc/modprobe.d/infinito-nfs-directory-delegations.conf
+        line: "options nfsv4 directory_delegations=N"
+        create: true
+        owner: root
+        group: root
+        mode: "0644"
+
+    - name: "🔧 Turn directory delegations off in the running kernel"
+      ansible.builtin.script:
+        cmd: "{{ lookup('path_absolute', 'roles/svc-storage-nfs-client/files/shell/directory_delegations.sh') }}"
+        executable: /bin/bash
+      register: svc_storage_nfs_client_directory_delegations
+      changed_when: "'CHANGED' in svc_storage_nfs_client_directory_delegations.stdout"

roles/svc-storage-nfs-client/tasks/main.yml

@@ -51,6 +51,10 @@
   failed_when:
     - svc_storage_nfs_client_probe is failed
 
+- name: "🔧 Align the NFS client's directory delegations with the ganesha server"
+  ansible.builtin.include_tasks: directory_delegations.yml
+  when: lookup('nfs_flavor') == 'ganesha'
+
 - name: "🔍 Probe-write a marker to confirm the mount is RW"
   ansible.builtin.copy:
     dest: "{{ SVC_STORAGE_NFS_CLIENT_PROBE_DIR }}/.svc-storage-nfs-client-probe.{{ inventory_hostname }}"

roles/svc-storage-nfs-server/tasks/03_controller_mount.yml

@@ -59,3 +59,7 @@
   retries: 12
   delay: 5
   until: _ctrl_nfs_mount is succeeded
+
+- name: "🔧 Align the controller's directory delegations with the ganesha server"
+  ansible.builtin.include_tasks: "{{ lookup('path_absolute', 'roles/svc-storage-nfs-client/tasks/directory_delegations.yml') }}"
+  when: lookup('nfs_flavor') == 'ganesha'