From ca916b9d1cc11db1288d568e316380b90219e36b Mon Sep 17 00:00:00 2001
From: Dean Wilson <dean.wilson@digital.cabinet-office.gov.uk>
Date: Mon, 16 May 2016 15:31:33 +0100
Subject: [PATCH 1/4] Add external collectd plugin.

This functionality is bundled in collect 5.5 but we have no current upgrade
plans or path so we'll use this for now
---
 .../files/usr/lib/collectd/file_handles.sh    | 33 +++++++++++++++++++
 1 file changed, 33 insertions(+)
 create mode 100644 modules/collectd/files/usr/lib/collectd/file_handles.sh

diff --git a/modules/collectd/files/usr/lib/collectd/file_handles.sh b/modules/collectd/files/usr/lib/collectd/file_handles.sh
new file mode 100644
index 0000000000..a20a5b2acd
--- /dev/null
+++ b/modules/collectd/files/usr/lib/collectd/file_handles.sh
@@ -0,0 +1,33 @@
+#!/bin/bash
+# Author: Phil Dufault (phil@dufault.info)
+# https://raw.githubusercontent.com/pdufault/collectd-exec-file_handles/master/file_handles.sh 
+# Commit 76e100799ae4d1cc231d0d343bd930f28d8d90c5
+# Date: April 2nd, 2014
+# Use: collectd exec script to collect system file handle metrics
+
+HOSTNAME="${COLLECTD_HOSTNAME:-`hostname -f`}"
+INTERVAL="${COLLECTD_INTERVAL:-10}"
+
+while sleep "$INTERVAL"; do
+
+  # Historically, the three values in file-nr denoted the number of
+  # * allocated file handles
+  # * the number of allocated but unused file handles
+  # * the maximum number of file handles.
+  # Linux 2.6 always reports 0 as the number of free file handles -- this is not an error, it just means that the number of allocated file handles exactly matches the number of used file handles.
+
+  # Grab the metrics
+  file_nr=($(cat /proc/sys/fs/file-nr))
+  allocated=${file_nr[0]}
+  allunused=${file_nr[1]}
+  max=${file_nr[2]}
+
+  # Output time
+  echo "PUTVAL $HOSTNAME/system-file_handles/gauge-file_handles_used interval=$INTERVAL N:$allocated"
+  echo "PUTVAL $HOSTNAME/system-file_handles/gauge-file_handles_allocatedunused interval=$INTERVAL N:$allunused"
+  echo "PUTVAL $HOSTNAME/system-file_handles/gauge-file_handles_max interval=$INTERVAL N:$max"
+
+  # putval format
+  #            <instance-id>/<plugin>-<plugin_instance>/<type>-<type_instance>
+
+done

From 4d33c965abeccabe1b807b255de824f4593ff53e Mon Sep 17 00:00:00 2001
From: Dean Wilson <dean.wilson@digital.cabinet-office.gov.uk>
Date: Mon, 16 May 2016 15:49:28 +0100
Subject: [PATCH 2/4] Puppet deploy a collectd file handle plugin

---
 .../collectd/manifests/plugin/file_handles.pp | 22 +++++++++++++++++++
 .../etc/collectd/conf.d/file_handles.conf.erb |  3 +++
 2 files changed, 25 insertions(+)
 create mode 100644 modules/collectd/manifests/plugin/file_handles.pp
 create mode 100644 modules/collectd/templates/etc/collectd/conf.d/file_handles.conf.erb

diff --git a/modules/collectd/manifests/plugin/file_handles.pp b/modules/collectd/manifests/plugin/file_handles.pp
new file mode 100644
index 0000000000..158c050f4c
--- /dev/null
+++ b/modules/collectd/manifests/plugin/file_handles.pp
@@ -0,0 +1,22 @@
+# == Class: collectd::plugin::file_handles
+#
+# Monitors the number of file handles in use on a system
+#
+class collectd::plugin::file_handles(
+) {
+
+  @file { '/usr/lib/collectd/file_handles.sh':
+    ensure  => 'present',
+    mode    => '0755',
+    owner   => 'root',
+    group   => 'root',
+    content => file('collectd/usr/lib/collectd/file_handles.sh'),
+    tag     => 'collectd::plugin',
+  }
+
+  @collectd::plugin { 'file_handles':
+    content => template('collectd/etc/collectd/conf.d/file_handles.conf.erb'),
+    require => File['/usr/lib/collectd/file_handles.sh'],
+  }
+
+}
diff --git a/modules/collectd/templates/etc/collectd/conf.d/file_handles.conf.erb b/modules/collectd/templates/etc/collectd/conf.d/file_handles.conf.erb
new file mode 100644
index 0000000000..33784b57dc
--- /dev/null
+++ b/modules/collectd/templates/etc/collectd/conf.d/file_handles.conf.erb
@@ -0,0 +1,3 @@
+<Plugin exec>
+  Exec nobody "/usr/lib/collectd/file_handles.sh"
+</Plugin>

From 14d5416a3397683c6b99e15ed64122555b47103c Mon Sep 17 00:00:00 2001
From: Dean Wilson <dean.wilson@digital.cabinet-office.gov.uk>
Date: Mon, 16 May 2016 16:44:21 +0100
Subject: [PATCH 3/4] Include the plugin on all nodes

---
 modules/collectd/manifests/config.pp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/modules/collectd/manifests/config.pp b/modules/collectd/manifests/config.pp
index 0922b9b8b6..567b1aca6d 100644
--- a/modules/collectd/manifests/config.pp
+++ b/modules/collectd/manifests/config.pp
@@ -36,6 +36,7 @@
     source => 'puppet:///modules/collectd/etc/collectd/conf.d/network.conf.client',
   }
 
+  include ::collectd::plugin::file_handles
   # Always collect basic processlist info.
   include ::collectd::plugin::processes
   include ::collectd::plugin::tcpconns

From 01a7d54b3edf9df447db97febf39d0270d7b2816 Mon Sep 17 00:00:00 2001
From: Dean Wilson <dean.wilson@digital.cabinet-office.gov.uk>
Date: Mon, 16 May 2016 17:21:31 +0100
Subject: [PATCH 4/4] Load the plugin

---
 .../templates/etc/collectd/conf.d/file_handles.conf.erb         | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/modules/collectd/templates/etc/collectd/conf.d/file_handles.conf.erb b/modules/collectd/templates/etc/collectd/conf.d/file_handles.conf.erb
index 33784b57dc..38ca60d308 100644
--- a/modules/collectd/templates/etc/collectd/conf.d/file_handles.conf.erb
+++ b/modules/collectd/templates/etc/collectd/conf.d/file_handles.conf.erb
@@ -1,3 +1,5 @@
+LoadPlugin exec
+
 <Plugin exec>
   Exec nobody "/usr/lib/collectd/file_handles.sh"
 </Plugin>