shrink-mon: support updating ceph config file after mon removal

This add the possibility for users to opt in/out about monitor removal
from the ceph config file on all nodes.

By default, it won't update the ceph config file. If you want the playbook
to update it, you have to pass the extra variable `-e shrink_mon_update_cfg=true`

Signed-off-by: Guillaume Abrioux <gabrioux@redhat.com>

infrastructure-playbooks/shrink-mon.yml

@@ -22,7 +22,7 @@
     - debug: msg="gather facts on all Ceph hosts for following reference"
 
 - name: confirm whether user really meant to remove monitor from the ceph cluster
-  hosts: "{{ groups[mon_group_name][0] }}"
+  hosts: localhost
   become: true
   vars_prompt:
     - name: ireallymeanit
@@ -33,115 +33,208 @@
     mon_group_name: mons
 
   pre_tasks:
-    - name: exit playbook, if only one monitor is present in cluster
+    - name: get current monitor status
-      fail:
+      delegate_to: "{{ groups.get(mon_group_name)[0] }}"
-        msg: "You are about to shrink the only monitor present in the cluster.
+      block:
-              If you really want to do that, please use the purge-cluster playbook."
+        - import_role:
-      when: groups[mon_group_name] | length | int == 1
+            name: ceph-defaults
 
-    - name: exit playbook, if no monitor was given
+        - import_role:
-      fail:
+            name: ceph-facts
-        msg: "mon_to_kill must be declared
+            tasks_from: container_binary
-          Exiting shrink-cluster playbook, no monitor was removed.
-           On the command line when invoking the playbook, you can use
-           -e mon_to_kill=ceph-mon01 argument. You can only remove a single monitor each time the playbook runs."
-      when: mon_to_kill is not defined
 
-    - name: exit playbook, if the monitor is not part of the inventory
+        - name: "set_fact container_exec_cmd build {{ container_binary }} exec command (containerized)"
-      fail:
+          set_fact:
-        msg: "It seems that the host given is not part of your inventory, please make sure it is."
+            container_exec_cmd: "{{ container_binary }} exec ceph-mon-{{ hostvars[groups.get(mon_group_name)[0]]['ansible_facts']['hostname'] }}"
-      when: mon_to_kill not in groups[mon_group_name]
+          when: containerized_deployment | bool
 
-    - name: exit playbook, if user did not mean to shrink cluster
+        - name: get current quorum status
-      fail:
+          command: "{{ container_exec_cmd }} ceph --cluster {{ cluster }} quorum_status -f json"
-        msg: "Exiting shrink-mon playbook, no monitor was removed.
+          changed_when: false
-           To shrink the cluster, either say 'yes' on the prompt or
+          failed_when: false
-           or use `-e ireallymeanit=yes` on the command line when
+          register: current_quorum_status
-           invoking the playbook"
-      when: ireallymeanit != 'yes'
 
-    - import_role:
-        name: ceph-defaults
-
-    - import_role:
-        name: ceph-facts
-        tasks_from: container_binary
-
-  tasks:
     - name: pick a monitor different than the one we want to remove
       set_fact:
         mon_host: "{{ item }}"
-      with_items: "{{ groups[mon_group_name] }}"
+      loop: "{{ (current_quorum_status.stdout | from_json)['quorum_names'] }}"
       when: item != mon_to_kill
 
-    - name: "set_fact container_exec_cmd build {{ container_binary }} exec command (containerized)"
+    - name: fail if basic requirements aren't satisfied
-      set_fact:
-        container_exec_cmd: "{{ container_binary }} exec ceph-mon-{{ hostvars[mon_host]['ansible_facts']['hostname'] }}"
-      when: containerized_deployment | bool
-
-    - name: exit playbook, if can not connect to the cluster
-      command: "{{ container_exec_cmd }} timeout 5 ceph --cluster {{ cluster }} health"
-      register: ceph_health
-      changed_when: false
-      until: ceph_health.stdout.find("HEALTH") > -1
       delegate_to: "{{ mon_host }}"
-      retries: 5
+      block:
-      delay: 2
+        - import_role:
+            name: ceph-defaults
 
-    - name: set_fact mon_to_kill_hostname
+        - import_role:
+            name: ceph-facts
+            tasks_from: container_binary
+
+        - name: "set_fact container_exec_cmd build {{ container_binary }} exec command (containerized)"
+          set_fact:
+            container_exec_cmd: "{{ container_binary }} exec ceph-mon-{{ hostvars[mon_host]['ansible_facts']['hostname'] }}"
+          when: containerized_deployment | bool
+
+        - name: exit playbook, if only one monitor is present in cluster
+          fail:
+            msg: "You are about to shrink the only monitor present in the cluster.
+                  If you really want to do that, please use the purge-cluster playbook."
+          when: groups[mon_group_name] | length | int == 1
+
+        - name: exit playbook, if no monitor was given
+          fail:
+            msg: "mon_to_kill must be declared
+              Exiting shrink-cluster playbook, no monitor was removed.
+               On the command line when invoking the playbook, you can use
+               -e mon_to_kill=ceph-mon01 argument. You can only remove a single monitor each time the playbook runs."
+          when: mon_to_kill is not defined
+
+        - name: exit playbook, if the monitor is not part of the inventory
+          fail:
+            msg: "It seems that the host given is not part of your inventory, please make sure it is."
+          when: mon_to_kill not in groups[mon_group_name]
+
+        - name: exit playbook, if user did not mean to shrink cluster
+          fail:
+            msg: "Exiting shrink-mon playbook, no monitor was removed.
+               To shrink the cluster, either say 'yes' on the prompt or
+               or use `-e ireallymeanit=yes` on the command line when
+               invoking the playbook"
+          when: ireallymeanit != 'yes'
+
+        - name: set_fact mon_to_kill_hostname
+          set_fact:
+            mon_to_kill_hostname: "{{ hostvars[mon_to_kill]['ansible_facts']['hostname'] }}"
+
+    - name: set_fact valid_mon_to_kill
       set_fact:
-        mon_to_kill_hostname: "{{ hostvars[mon_to_kill]['ansible_facts']['hostname'] }}"
+        valid_mon_to_kill: "{{ mon_to_kill_hostname in (current_quorum_status.stdout | from_json)['quorum_names'] }}"
 
-    - name: stop monitor service(s)
-      service:
-        name: ceph-mon@{{ mon_to_kill_hostname }}
-        state: stopped
-        enabled: no
-      delegate_to: "{{ mon_to_kill }}"
-      failed_when: false
 
-    - name: purge monitor store
+  tasks:
-      file:
+    - name: shrink selected monitor
-        path: /var/lib/ceph/mon/{{ cluster }}-{{ mon_to_kill_hostname }}
-        state: absent
-      delegate_to: "{{ mon_to_kill }}"
-
-    - name: remove monitor from the quorum
-      command: "{{ container_exec_cmd }} ceph --cluster {{ cluster }} mon remove {{ mon_to_kill_hostname }}"
-      changed_when: false
-      failed_when: false
       delegate_to: "{{ mon_host }}"
+      when: valid_mon_to_kill | bool
+      block:
+        - name: exit playbook, if can not connect to the cluster
+          command: "{{ container_exec_cmd }} timeout 5 ceph --cluster {{ cluster }} health"
+          register: ceph_health
+          changed_when: false
+          until: ceph_health.stdout.find("HEALTH") > -1
+          retries: 5
+          delay: 2
+
+        - name: stop monitor service(s)
+          service:
+            name: ceph-mon@{{ mon_to_kill_hostname }}
+            state: stopped
+            enabled: no
+          delegate_to: "{{ mon_to_kill }}"
+          failed_when: false
+
+        - name: purge monitor store
+          file:
+            path: /var/lib/ceph/mon/{{ cluster }}-{{ mon_to_kill_hostname }}
+            state: absent
+          delegate_to: "{{ mon_to_kill }}"
+
+        - name: remove monitor from the quorum
+          command: "{{ container_exec_cmd }} ceph --cluster {{ cluster }} mon remove {{ mon_to_kill_hostname }}"
+          changed_when: false
+          failed_when: false
 
   post_tasks:
-    - name: verify the monitor is out of the cluster
+    - name: post verifications
-      command: "{{ container_exec_cmd }} ceph --cluster {{ cluster }} quorum_status -f json"
       delegate_to: "{{ mon_host }}"
-      changed_when: false
+      when: valid_mon_to_kill | bool
-      failed_when: false
+      block:
-      register: result
+        - name: verify the monitor is out of the cluster
-      until: mon_to_kill_hostname not in (result.stdout | from_json)['quorum_names']
+          command: "{{ container_exec_cmd }} ceph --cluster {{ cluster }} quorum_status -f json"
-      retries: 2
+          changed_when: false
-      delay: 10
+          failed_when: false
+          register: result
+          until: mon_to_kill_hostname not in (result.stdout | from_json)['quorum_names']
+          retries: 2
+          delay: 10
 
-    - name: please remove the monitor from your ceph configuration file
+        - name: fail if monitor is still part of the cluster
-      debug:
+          fail:
-          msg: "The monitor has been successfully removed from the cluster.
+              msg: "Monitor appears to still be part of the cluster, please check what happened."
-          Please remove the monitor entry from the rest of your ceph configuration files, cluster wide."
+          run_once: true
-      run_once: true
+          when: mon_to_kill_hostname in (result.stdout | from_json)['quorum_names']
-      when: mon_to_kill_hostname not in (result.stdout | from_json)['quorum_names']
 
-    - name: fail if monitor is still part of the cluster
+- name: remove monitor entry from ceph config file
-      fail:
+  hosts:
-          msg: "Monitor appears to still be part of the cluster, please check what happened."
+    - mons
-      run_once: true
+    - osds
-      when: mon_to_kill_hostname in (result.stdout | from_json)['quorum_names']
+    - mdss
+    - rgws
+    - nfss
+    - rbdmirrors
+    - clients
+    - iscsigws
+    - mgrs
+    - monitoring
+  gather_facts: false
+  become: True
+  any_errors_fatal: true
+  tasks:
+    - name: update ceph config file
+      when:
+        - shrink_mon_update_cfg | default(false) | bool
+        - hostvars['localhost']['valid_mon_to_kill'] | bool
+      block:
+        - name: gather and delegate facts
+          setup:
+            gather_subset:
+              - 'all'
+              - '!facter'
+              - '!ohai'
+          delegate_to: "{{ item }}"
+          delegate_facts: True
+          with_items: "{{ groups['all'] | difference(groups.get('clients', [])) }}"
+          run_once: true
+          tags: always
 
-    - name: show ceph health
+        - import_role:
-      command: "{{ container_exec_cmd }} ceph --cluster {{ cluster }} -s"
+            name: ceph-defaults
+
+        - import_role:
+            name: ceph-facts
+
+        - import_role:
+            name: ceph-handler
+
+        - import_role:
+            name: ceph-config
+
+
+- name: show ceph status
+  hosts: localhost
+  become: true
+  tasks:
+    - name: show ceph status
       delegate_to: "{{ mon_host }}"
-      changed_when: false
+      block:
+        - import_role:
+            name: ceph-defaults
 
-    - name: show ceph mon status
+        - name: set_fact ceph_cmd
-      command: "{{ container_exec_cmd }} ceph --cluster {{ cluster }} mon stat"
+          set_fact:
-      delegate_to: "{{ mon_host }}"
+            ceph_cmd: "{{ container_binary + ' run --rm --net=host -v /etc/ceph:/etc/ceph:z -v /var/lib/ceph:/var/lib/ceph:ro -v /var/run/ceph:/var/run/ceph:z --entrypoint=ceph ' + ceph_docker_registry + '/' + ceph_docker_image + ':' + ceph_docker_image_tag if containerized_deployment | bool else 'ceph' }} --cluster {{ cluster }}"
-      changed_when: false
+
+        - name: show ceph mon status
+          command: "{{ ceph_cmd }} mon stat"
+          changed_when: false
+
+        - name: show ceph health
+          command: "{{ ceph_cmd }} -s"
+          changed_when: false
+
+        - name: warn about ceph config file
+          fail:
+            msg: |
+              `shrink_mon_update_cfg` wasn't set to `true`.
+              Please, update manually your ceph config file on all nodes or rerun this playbook with `-e shrink_mon_update_cfg=true`
+          when: not shrink_mon_update_cfg | default(false) | bool
+          ignore_errors: true

roles/ceph-config/templates/ceph.conf.j2

@@ -23,7 +23,7 @@ osd crush chooseleaf type = 0
 {% endif %}
 
 {% if nb_mon > 0 and inventory_hostname in groups.get(mon_group_name, []) %}
-mon initial members = {% for host in groups[mon_group_name] %}
+mon initial members = {% for host in groups[mon_group_name] | difference([mon_to_kill | default('')]) %}
       {% if hostvars[host]['ansible_facts']['hostname'] is defined -%}
         {{ hostvars[host]['ansible_facts']['hostname'] }}
       {%- endif %}

roles/ceph-facts/tasks/set_monitor_address.yml

@@ -2,7 +2,7 @@
 - name: set_fact _monitor_addresses to monitor_address_block ipv4
   set_fact:
     _monitor_addresses: "{{ _monitor_addresses | default([]) + [{ 'name': item, 'addr': hostvars[item]['ansible_facts']['all_ipv4_addresses'] | ips_in_ranges(hostvars[item]['monitor_address_block'].split(',')) | first }] }}"
-  with_items: "{{ groups.get(mon_group_name, []) }}"
+  loop: "{{ groups.get(mon_group_name, []) | difference(mon_to_kill | default('')) }}"
   when:
     - "item not in _monitor_addresses | default([]) | selectattr('name', 'defined') |  map(attribute='name') | list"
     - hostvars[item]['monitor_address_block'] is defined
@@ -12,7 +12,7 @@
 - name: set_fact _monitor_addresses to monitor_address_block ipv6
   set_fact:
     _monitor_addresses: "{{ _monitor_addresses | default([]) + [{ 'name': item, 'addr': hostvars[item]['ansible_facts']['all_ipv6_addresses'] | ips_in_ranges(hostvars[item]['monitor_address_block'].split(',')) | last | ansible.utils.ipwrap }] }}"
-  with_items: "{{ groups.get(mon_group_name, []) }}"
+  loop: "{{ groups.get(mon_group_name, []) | difference(mon_to_kill | default('')) }}"
   when:
     - "item not in _monitor_addresses | default([]) | selectattr('name', 'defined') |  map(attribute='name') | list"
     - hostvars[item]['monitor_address_block'] is defined
@@ -22,7 +22,7 @@
 - name: set_fact _monitor_addresses to monitor_address
   set_fact:
     _monitor_addresses: "{{ _monitor_addresses | default([]) + [{ 'name': item, 'addr': hostvars[item]['monitor_address'] | ansible.utils.ipwrap}] }}"
-  with_items: "{{ groups.get(mon_group_name, []) }}"
+  loop: "{{ groups.get(mon_group_name, []) | difference(mon_to_kill | default('')) }}"
   when:
     - "item not in _monitor_addresses | default([]) | selectattr('name', 'defined') | map(attribute='name') | list"
     - hostvars[item]['monitor_address'] is defined
@@ -31,7 +31,7 @@
 - name: set_fact _monitor_addresses to monitor_interface - ipv4
   set_fact:
     _monitor_addresses: "{{ _monitor_addresses | default([]) + [{ 'name': item, 'addr': hostvars[item]['ansible_facts'][(hostvars[item]['monitor_interface']|replace('-', '_'))][ip_version]['address'] | ansible.utils.ipwrap }]  }}"
-  with_items: "{{ groups.get(mon_group_name, []) }}"
+  loop: "{{ groups.get(mon_group_name, []) | difference(mon_to_kill | default('')) }}"
   when:
     - "item not in _monitor_addresses | default([]) | selectattr('name', 'defined') | map(attribute='name') | list"
     - ip_version == 'ipv4'
@@ -42,7 +42,7 @@
 - name: set_fact _monitor_addresses to monitor_interface - ipv6
   set_fact:
     _monitor_addresses: "{{ _monitor_addresses | default([]) + [{ 'name': item, 'addr': hostvars[item]['ansible_facts'][(hostvars[item]['monitor_interface']|replace('-', '_'))][ip_version][0]['address'] | ansible.utils.ipwrap }] }}"
-  with_items: "{{ groups.get(mon_group_name, []) }}"
+  loop: "{{ groups.get(mon_group_name, []) | difference(mon_to_kill | default('')) }}"
   when:
     - "item not in _monitor_addresses | default([]) | selectattr('name', 'defined') | map(attribute='name') | list"
     - ip_version == 'ipv6'

tox.ini

@@ -118,6 +118,7 @@ commands=
   ansible-playbook -vv -i {changedir}/{env:INVENTORY} {toxinidir}/infrastructure-playbooks/shrink-mon.yml --extra-vars "\
       ireallymeanit=yes \
       mon_to_kill={env:MON_TO_KILL:mon2} \
+      shrink_mon_update_cfg=true \
   "
 [shrink-osd]
 commands=