From d8538ad4e16fe76d63e607491d41793303f929b1 Mon Sep 17 00:00:00 2001
From: Dimitri Savineau <dsavinea@redhat.com>
Date: Thu, 7 Mar 2019 17:14:12 -0500
Subject: [PATCH] Set the default crush rule in ceph.conf

Currently the default crush rule value is added to the ceph config
on the mon nodes as an extra configuration applied after the template
generation via the ansible ini module.

This implies two behaviors:

1/ On each ceph-ansible run, the ceph.conf will be regenerated via
ceph-config+template and then ceph-mon+ini_file. This leads to a
non necessary daemons restart.

2/ When other ceph daemons are collocated on the monitor nodes
(like mgr or rgw), the default crush rule value will be erased by
the ceph.conf template (mon -> mgr -> rgw).

This patch adds the osd_pool_default_crush_rule config to the ceph
template and only for the monitor nodes (like crush_rules.yml).
The default crush rule id is read (if exist) from the current ceph
configuration.
The default configuration is -1 (ceph default).

Closes: https://bugzilla.redhat.com/show_bug.cgi?id=1638092

Signed-off-by: Dimitri Savineau <dsavinea@redhat.com>
---
 roles/ceph-config/templates/ceph.conf.j2 |  2 ++
 roles/ceph-defaults/vars/main.yml        |  1 +
 roles/ceph-facts/tasks/facts.yml         | 17 +++++++++++++++++
 roles/ceph-mon/tasks/crush_rules.yml     |  8 ++------
 4 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/roles/ceph-config/templates/ceph.conf.j2 b/roles/ceph-config/templates/ceph.conf.j2
index 64df04634..2ce9afb32 100644
--- a/roles/ceph-config/templates/ceph.conf.j2
+++ b/roles/ceph-config/templates/ceph.conf.j2
@@ -32,6 +32,8 @@ mon initial members = {% for host in groups[mon_group_name] %}
       {%- endif %}
       {%- if not loop.last %},{% endif %}
     {% endfor %}
+
+osd pool default crush rule = {{ osd_pool_default_crush_rule | default(ceph_osd_pool_default_crush_rule) }}
 {% endif %}
 
 fsid = {{ fsid }}
diff --git a/roles/ceph-defaults/vars/main.yml b/roles/ceph-defaults/vars/main.yml
index f757d66f7..794e3ad0a 100644
--- a/roles/ceph-defaults/vars/main.yml
+++ b/roles/ceph-defaults/vars/main.yml
@@ -2,3 +2,4 @@
 ceph_osd_pool_default_size: 3
 ceph_osd_pool_default_min_size: 0
 ceph_osd_pool_default_pg_num: 8
+ceph_osd_pool_default_crush_rule: -1
diff --git a/roles/ceph-facts/tasks/facts.yml b/roles/ceph-facts/tasks/facts.yml
index 3d4ff808e..bbb041a86 100644
--- a/roles/ceph-facts/tasks/facts.yml
+++ b/roles/ceph-facts/tasks/facts.yml
@@ -249,6 +249,23 @@
   set_fact:
     osd_pool_default_min_size: "{{ ceph_conf_overrides.get('global', {}).get('osd_pool_default_min_size', ceph_osd_pool_default_min_size) }}"
 
+- name: check if the ceph conf exists
+  stat:
+    path: '/etc/ceph/{{ cluster }}.conf'
+  register: ceph_conf
+
+- name: get default crush rule value from ceph configuration
+  command: grep 'osd pool default crush rule' /etc/ceph/{{ cluster }}.conf
+  register: crush_rule_variable
+  changed_when: false
+  failed_when: false
+  when: ceph_conf.stat.exists
+
+- name: set_fact osd_pool_default_crush_rule
+  set_fact:
+    osd_pool_default_crush_rule: "{% if crush_rule_variable.rc == 0 %}{{ crush_rule_variable.stdout.split(' = ')[1] }}{% else %}{{ ceph_osd_pool_default_crush_rule }}{% endif %}"
+  when: ceph_conf.stat.exists
+
 - name: import_tasks set_monitor_address.yml
   import_tasks: set_monitor_address.yml
 
diff --git a/roles/ceph-mon/tasks/crush_rules.yml b/roles/ceph-mon/tasks/crush_rules.yml
index 2da7e8254..18428ecdd 100644
--- a/roles/ceph-mon/tasks/crush_rules.yml
+++ b/roles/ceph-mon/tasks/crush_rules.yml
@@ -38,12 +38,8 @@
     - inventory_hostname == groups.get(mon_group_name) | last
     - not item.get('skipped', false)
 
-- name: set_fact osd_pool_default_crush_rule
-  set_fact:
-    osd_pool_default_crush_rule: "osd_pool_default_crush_rule"
-
 - name: insert new default crush rule into daemon to prevent restart
-  command: "{{ hostvars[item]['docker_exec_cmd'] | default('') }} ceph --cluster {{ cluster }} daemon mon.{{ hostvars[item]['monitor_name'] }} config set {{ osd_pool_default_crush_rule }} {{ info_ceph_default_crush_rule_yaml.rule_id }}"
+  command: "{{ hostvars[item]['docker_exec_cmd'] | default('') }} ceph --cluster {{ cluster }} daemon mon.{{ hostvars[item]['monitor_name'] }} config set osd_pool_default_crush_rule {{ info_ceph_default_crush_rule_yaml.rule_id }}"
   changed_when: false
   delegate_to: "{{ item }}"
   with_items: "{{ groups[mon_group_name] }}"
@@ -55,7 +51,7 @@
   ini_file:
     dest: "/etc/ceph/{{ cluster }}.conf"
     section: "global"
-    option: "{{ osd_pool_default_crush_rule }}"
+    option: "osd pool default crush rule"
     value: "{{ info_ceph_default_crush_rule_yaml.rule_id }}"
   delegate_to: "{{ item }}"
   with_items: "{{ groups[mon_group_name] }}"