memcached: NRPE check for multi-instance setup

Also some cleanup & split of tasks between single and multi instance

Note: Munin part seems still broken at the time

CHANGELOG.md

@@ -17,6 +17,7 @@ The **patch** part changes is incremented if multiple releases happen the same m
 * vrrp: add an `ip.yml` task file to help create VRRP addresses
 * webapps/nextcloud: Add compatibility with apache2, and apache2 mod_php.
 * inspect-domains: Add role
+* memcached: NRPE check for multi-instance setup
 
 ### Changed
 

memcached/files/check_memcached_instances.sh

@@ -0,0 +1,82 @@
+#!/bin/sh
+
+# {{ ansible_managed }}
+
+set -u
+
+return=0
+nb_crit=0
+nb_warn=0
+nb_ok=0
+nb_unchk=0
+output=""
+
+vendored_check=/usr/local/lib/nagios/plugins/check_memcached.pl
+
+if [ -x $vendored_check ]; then
+    check_bin=$vendored_check
+else
+    echo "UNCHK - can't find check_memcached"
+    exit 3
+fi
+
+check_server() {
+    name=$1
+    conf_file=$2
+
+    host=$(config_var "-l" "${conf_file}")
+    port=$(config_var "-p" "${conf_file}")
+
+    cmd="${check_bin} -H ${host} -p ${port}"
+
+    result=$($cmd)
+    ret="${?}"
+    if [ "${ret}" -ge 2 ]; then
+        nb_crit=$((nb_crit + 1))
+        printf -v output "%s%s\n" "${output}" "${result}"
+        [ "${return}" -le 2 ] && return=2
+    elif [ "${ret}" -ge 1 ]; then
+        nb_warn=$((nb_warn + 1))
+        printf -v output "%s%s\n" "${output}" "${result}"
+        [ "${return}" -le 1 ] && return=1
+    else
+        nb_ok=$((nb_ok + 1))
+        printf -v output "%s%s\n" "${output}" "${result}"
+        [ "${return}" -le 0 ] && return=0
+    fi
+}
+config_var() {
+    variable=$1
+    file=$2
+    test -f "${file}" && grep -E "^${variable}\s+.+$" "${file}" | awk '{ print $2 }' | sed -e "s/^[\"']//" -e "s/[\"']$//"
+}
+
+# default instance
+if systemctl is-enabled -q memcached; then
+    check_server "default" "/etc/memcached.conf"
+fi
+
+# additional instances
+conf_files=$(ls -1 /etc/memcached_*.conf 2> /dev/null)
+for conf_file in ${conf_files}; do
+    name=$(basename "${conf_file}" | sed '{s|memcached_||;s|\.conf||}')
+    if systemctl is-enabled -q "memcached@${name}.service"; then
+        check_server "${name}" "${conf_file}"
+    else
+        nb_unchk=$((nb_unchk + 1))
+        output="${output}UNCHK - ${name} (unit is disabled or missing)\n"
+    fi
+done
+
+[ "${return}" -ge 0 ] && header="OK"
+[ "${return}" -ge 1 ] && header="WARNING"
+[ "${return}" -ge 2 ] && header="CRITICAL"
+
+printf "%s - %s UNCHK / %s CRIT / %s WARN / %s OK\n\n" "${header}" "${nb_unchk}" "${nb_crit}" "${nb_warn}" "${nb_ok}"
+
+printf "%s" "${output}" | grep -E "CRITICAL"
+printf "%s" "${output}" | grep -E "WARNING"
+printf "%s" "${output}" | grep -E "OK"
+printf "%s" "${output}" | grep -E "UNCHK"
+
+exit "${return}"

memcached/tasks/instance-default.yml

@@ -0,0 +1,17 @@
+
+- name: Memcached is configured.
+  template:
+    src: memcached.conf.j2
+    dest: /etc/memcached.conf
+    mode: "0644"
+  notify: restart memcached
+  tags:
+    - memcached
+
+- name: Memcached is running and enabled on boot.
+  service:
+    name: memcached
+    enabled: yes
+    state: started
+  tags:
+    - memcached

memcached/tasks/instance-multi.yml

@@ -0,0 +1,41 @@
+---
+
+- name: Add systemd unit template
+  copy:
+    src: memcached@.service
+    dest: /etc/systemd/system/memcached@.service
+  tags:
+    - memcached
+
+- name: Disable default memcached systemd unit
+  systemd:
+    name: memcached
+    enabled: false
+    state: stopped
+  tags:
+    - memcached
+
+- name: Make sure memcached.conf is absent
+  file:
+    path: /etc/memcached.conf
+    state: absent
+  tags:
+    - memcached
+
+- name: "Create a configuration file for instance ({{ memcached_instance_name }})"
+  template:
+    src: memcached.conf.j2
+    dest: /etc/memcached_{{ memcached_instance_name }}.conf
+    mode: "0644"
+  tags:
+    - memcached
+
+- name: "Enable and start the memcached instance ({{ memcached_instance_name }})"
+  systemd:
+    name: memcached@{{ memcached_instance_name }}
+    enabled: yes
+    state: started
+    daemon_reload: yes
+    masked: no
+  tags:
+    - memcached

memcached/tasks/main.yml

@@ -1,73 +1,15 @@
-- name: ensure packages are installed
+- name: Ensure memcached is installed
   apt:
     name: memcached
     state: present
   tags:
     - memcached
 
-- name: Memcached is configured.
-  template:
-    src: memcached.conf.j2
-    dest: /etc/memcached.conf
-    mode: "0644"
-  notify: restart memcached
-  tags:
-    - memcached
-  when: memcached_instance_name | length == 0
-
-- name: Memcached is running and enabled on boot.
-  service:
-    name: memcached
-    enabled: yes
-    state: started
-  tags:
-    - memcached
-  when: memcached_instance_name | length == 0
+- include: instance-default.yml
+  when: memcached_instance_name is undefined
 
-- name: Add systemd template
-  copy:
-    src: memcached@.service
-    dest: /etc/systemd/system/memcached@.service
-  tags:
-    - memcached
-  when: memcached_instance_name | length > 0
-
-- name: Delete default memcached systemd configuration file
-  systemd:
-    name: memcached
-    enabled: false
-    state: stopped
-  tags:
-    - memcached
-  when: memcached_instance_name | length > 0
-
-- name: Make sure memcached.conf is absent
-  file:
-    path: /etc/memcached.conf
-    state: absent
-  tags:
-    - memcached
-  when: memcached_instance_name | length > 0
-
-- name: Create a configuration file
-  template:
-    src: memcached.conf.j2
-    dest: /etc/memcached_{{ memcached_instance_name }}.conf
-    mode: "0644"
-  tags:
-    - memcached
-  when: memcached_instance_name | length > 0
-
-- name: Enable and start the memcached instance
-  systemd:
-    name: memcached@{{ memcached_instance_name }}
-    enabled: yes
-    state: started
-    daemon_reload: yes
-    masked: no
-  tags:
-    - memcached
-  when: memcached_instance_name | length > 0
+- include: instance-multi.yml
+  when: memcached_instance_name is defined
 
 - include: munin.yml
 

memcached/tasks/munin.yml

@@ -2,7 +2,7 @@
 - name: Choose packages (Oracle)
   set_fact:
      multi: "multi_"
-  when: memcached_instance_name | length > 0
+  when: memcached_instance_name is defined
 
 - name: is Munin present ?
   stat:

memcached/tasks/nrpe.yml

@@ -1,6 +1,4 @@
 ---
-- include_role:
-    name: evolix/remount-usr
 
 - name: Is nrpe present ?
   stat:
@@ -10,7 +8,12 @@
 - block:
   - name: Install dependencies
     apt:
-      name: libcache-memcached-perl
+      name: 
+      - libcache-memcached-perl
+      - libmemcached11
+
+  - include_role:
+      name: evolix/remount-usr
 
   - name: Copy Nagios check for memcached
     copy:
@@ -18,13 +21,29 @@
       dest: /usr/local/lib/nagios/plugins/
       mode: "0755"
 
-  # TODO: install a "multi-instances" check if the memcached_instance_name variable is not null
+  - name: install check_memcached_instances
+    copy:
+      src: check_memcached_instances.sh
+      dest: /usr/local/lib/nagios/plugins/check_memcached_instances
+      force: yes
+      mode: "0755"
+      owner: root
+      group: root
 
-  - name: Add NRPE check
+  - name: Add NRPE check (single instance)
     lineinfile:
       name: /etc/nagios/nrpe.d/evolix.cfg
       regexp: '^command\[check_memcached\]='
       line: 'command[check_memcached]=/usr/local/lib/nagios/plugins/check_memcached.pl -H 127.0.0.1 -p {{ memcached_port }}'
     notify: restart nagios-nrpe-server
+    when: memcached_instance_name is undefined
+
+  - name: Add NRPE check (multi instance)
+    lineinfile:
+      name: /etc/nagios/nrpe.d/evolix.cfg
+      regexp: '^command\[check_memcached\]='
+      line: 'command[check_memcached]=/usr/local/lib/nagios/plugins/check_memcached_instances'
+    notify: restart nagios-nrpe-server
+    when: memcached_instance_name is defined
 
   when: nrpe_evolix_config.stat.exists