collectd curl_json plugin configuration to pull MongoDB statistics from the REST interface. This requires collectd to be compiled with curl_json or have the plugin installed. This has been tested with MongoDB 2.4.4. Optional metrics have been commented out, though can be easily enabled.

mongodb_json_curl.conf

## Load curl_json plugin
LoadPlugin curl_json

<Plugin curl_json>
  <URL "http://localhost:28017/serverStatus?text=1">
    Instance "mongodb"

## Specify JSON array keys to collect information



# Asserts
# The asserts document reports the number of assertions or errors produced by the server

   <Key "asserts/regular">
           Type "gauge"
   </Key>

   <Key "asserts/warning">
           Type "gauge"
   </Key>

   <Key "asserts/mgs">
           Type "gauge"
   </Key>

   <Key "asserts/user">
           Type "gauge"
   </Key>

   <Key "asserts/regular">
           Type "gauge"
   </Key>



# Background Flushing Statistics
# The backgroundFlushing document reports on the process MongoDB uses to write data to disk

   <Key "backgroundFlushing/flushes">
           Type "gauge"
   </Key>

   <Key "backgroundFlushing/total_ms">
           Type "gauge"
   </Key>

   <Key "backgroundFlushing/average_ms">
           Type "gauge"
   </Key>

   <Key "backgroundFlushing/last_ms">
           Type "gauge"
   </Key>


# Connections
# The connections field reports on MongoDB’s current memory use by the MongoDB process.


   <Key "connections/current">
           Type "gauge"
   </Key>

   <Key "connections/available">
           Type "gauge"
   </Key>

   <Key "connections/totalCreated">
           Type "gauge"
   </Key>



# Cursors
# The cursors document reports on current cursor use and state.

   <Key "cursors/totalOpen">
           Type "gauge"
   </Key>

   <Key "cursors/ClientCursors_size">
           Type "gauge"
   </Key>

   <Key "cursors/timedOut">
           Type "gauge"
   </Key>

   <Key "cursors/totalNoTimeout">
           Type "gauge"
   </Key>


# Global Lock
# The globalLock field reports on MongoDB’s global system lock.
# In most cases the locks document provides more fine grained data that reflects lock use.


   <Key "globalLock/totalTime">
           Type "gauge"
   </Key>

   <Key "globalLock/lockTime">
           Type "gauge"
   </Key>

   <Key "globalLock/currentQueue/total">
           Type "gauge"
   </Key>

   <Key "globalLock/currentQueue/readers">
           Type "gauge"
   </Key>

   <Key "globalLock/currentQueue/writers">
           Type "gauge"
   </Key>

  <Key "globalLock/activeClients/total">
          Type "gauge"
  </Key>

   <Key "globalLock/activeClients/readers">
           Type "gauge"
   </Key>

   <Key "globalLock/activeClients/writers">
           Type "gauge"
   </Key>


# Index Counters
# The indexCounters document reports on index use


   <Key "indexCounters/accesses">
           Type "gauge"
   </Key>

   <Key "indexCounters/hits">
           Type "gauge"
   </Key>

   <Key "indexCounters/misses">
           Type "gauge"
   </Key>

   <Key "indexCounters/resets">
           Type "gauge"
   </Key>

   <Key "indexCounters/missRatio">
           Type "gauge"
   </Key>


# Network Statistics
# The network document reports on network use and state

   <Key "network/bytesIn">
           Type "gauge"
   </Key>

   <Key "network/bytesOut">
           Type "gauge"
   </Key>

   <Key "network/numRequests">
           Type "gauge"
   </Key>


# Operation Counters (opcounters)
# The opcounters document reports the number of operations this MongoDB instance has processed


   <Key "opcounters/insert">
           Type "gauge"
   </Key>

   <Key "opcounters/query">
           Type "gauge"
   </Key>

   <Key "opcounters/update">
           Type "gauge"
   </Key>

   <Key "opcounters/delete">
           Type "gauge"
   </Key>

   <Key "opcounters/getmore">
           Type "gauge"
   </Key>

   <Key "opcounters/command">
           Type "gauge"
   </Key>



# Replication Operation Counters (opcounters)
# The opcountersRepl document reports the number of replicated operations


   <Key "opcountersRepl/insert">
           Type "gauge"
   </Key>

   <Key "opcountersRepl/query">
           Type "gauge"
   </Key>

   <Key "opcountersRepl/update">
           Type "gauge"
   </Key>

   <Key "opcountersRepl/delete">
           Type "gauge"
   </Key>

   <Key "opcountersRepl/getmore">
           Type "gauge"
   </Key>

   <Key "opcountersRepl/command">
           Type "gauge"
   </Key>


# Memory Use Statistics
# The mem field reports on MongoDB’s current memory use

   <Key "mem/bits">
           Type "gauge"
   </Key>

   <Key "mem/resident">
           Type "gauge"
   </Key>

   <Key "mem/virtual">
           Type "gauge"
   </Key>

   <Key "mem/supported">
           Type "gauge"
   </Key>

   <Key "mem/mapped">
           Type "gauge"
   </Key>      

   <Key "mem/mappedWithJournal">
           Type "gauge"
   </Key>      


# Service Metrics
# The metrics document contains a number of operational metrics that are useful for monitoring the state and workload of a mongod instance.

#  <Key "metrics/*/*/*/*">
#          Type "gauge"
#  </Key>     



  </URL>
</Plugin>