Pandora FMSAdministrator Manual

MongoDB Monitoring

Administrator Manual MongoDB Monitoring

© Artica Soluciones Tecnológicas 2005-2012

Index1Changelog...........................................................................................................................................32Introduction........................................................................................................................................43Compatibility matrix .........................................................................................................................54Documentation provided by the requesting area................................................................................65Modules provided by MongoDB plugin ............................................................................................76Requisites ..........................................................................................................................................8

6.1.Configuration of the MongoDB instance...................................................................................87File Configuration..............................................................................................................................98Installing...........................................................................................................................................109Configuration and deployment.........................................................................................................11

1 CHANGELOG

Date Author Change Version

22/11/12 Tomas First version v1r1

2 INTRODUCTION

Page 3

The main objective of this document is the description of the MongoDB database monitoring

procedures on Linux-based systems. We have chosen a set of “base” modules based on our

experience in system monitoring and on the needs of some of our clients.

To extract the information we use:

• An external configuration file where all the plugin parameterization is defined.

• We use the software already installed in the system (mongo, mongostat, awk, grep, etc), for

the monitoring done by the plugin without having to install libraries or third party tools.

• The system is integrated with the Unix agent and with the capacity of distributing file

collections. That way it is posible to distribute the plugin on the one hand and the file

collections in an individual way-by agent-and/or by policies on the other hand.

3 COMPATIBILITY MATRIX

The compatibility matrix for MongoDB monitoring is:

Page 4

Systems where it has been tested • MongoDB v2.2.1

Systems where it should work • MongoDB v2.0.8 or above

4 DOCUMENTATION PROVIDED BY THE REQUESTING AREA

In order to get the MongoDB monitoring done correctly, it is necessary that the technical Area sends some

specific information that will be included in the configuration files. This information is the following:

Page 5

• Port where the MongoDB database is listening.

• Credentials needed to connect to the database, if any.

• MongoDB Config Server port.

• Name of the MongoDB database (case sensitive!).

• MongoDB instance listening IP.

5 MODULES PROVIDED BY MONGODB PLUGIN This plugin returns 16 modules by instance. All of them generate status graphs. You should fix

thresholds manually to determine whether something is in a warning/critical operative.

• MongoDB_Inserts_$CFG_HOST:$CFG_PORT: DB Inserts per second for this

instance.

Page 6

• MongoDB_Queries_$CFG_HOST:$CFG_PORT: DB Queries per second for this

instance.

• MongoDB_Updates_$CFG_HOST:$CFG_PORT: DB Updates per second for this

instance.

• MongoDB_Deletes_$CFG_HOST:$CFG_PORT: DB Deletes per second for this

instance.

• MongoDB_Getmores_$CFG_HOST:$CFG_PORT: DB Getmores per second for this

instance.

• MongoDB_Commands_$CFG_HOST:$CFG_PORT: DB Commands per second for

this instance.

• MongoDB_Flushes_$CFG_HOST:$CFG_PORT: DB Fsync flushes per second for

this instance.

• MongoDB_PageFaults_$CFG_HOST:$CFG_PORT: DB Page faults per second for

this instance.

• MongoDB_IdxMiss_$CFG_HOST:$CFG_PORT: DB bttree page missed percentage

for this instance.

• MongoDB_ClientReadQueueLength_$CFG_HOST:$CFG_PORT: DB Client read

queue length for this instance.

• MongoDB_ClientWriteQueueLength_$CFG_HOST:$CFG_PORT: DB Client write

queue length for this instance.

• MongoDB_ActiveClientsReading_$CFG_HOST:$CFG_PORT: DB Active reading

clients for this instance.

• MongoDB_ActiveClientsWriting_$CFG_HOST:$CFG_PORT: DB Active writing

clients for this instance.

• MongoDB_NetworkTrafficInBits_$CFG_HOST:$CFG_PORT: DB Network traffic

in bits for this instance.

• MongoDB_NetworkTrafficOutBits_$CFG_HOST:$CFG_PORT: DB Network

traffic out bits for this instance.

• MongoDB_OpenConns_$CFG_HOST:$CFG_PORT: DB Open connections for this

instance.

6 REQUISITES The MongoDB monitoring is done basically getting data through MongoDB system command

mongostat and through the execution of commands in the Operative System.

Page 7

The requisites to this monitoring could work correctly are the followings:

• To install the Pandora agent (>3.2.1)

• MongoDB instance configuration to accept connections using mongostat.

• Mongo bin folder (where mongostat resides) must be located in the user PATH.

6.1. Configuration of the MongoDB instance

In this section is explained how to deploy and start a MongoDB instance in a Linux-based server. If

you want to deploy multiple instances and monitor sharding controllers, please keep in mind that

this kind of MongoDB instance currently doesn't provide all the information mentioned above, but

a limited set of modules. The steps required to achieve this are simple: are the following: first find

the MongoDB daemon (mongod) and start up as many instances as you need, providing the

listening port, DB path and instance role as parameters:

• Instance startup sample: mongod --rest --dbpath /data/sharddb --shardsvr >&

/var/log/mongoshardsvr.log & (in this case the default port for shard svrs, 27018, is used)

The following document explains how to display and configure the MongoDB instance properly:

http://docs.mongodb.org/manual/administration/configuration/

However, the monitoring system will be able to work right after the instance startup, without

having to wait for additional configuration.

7 FILE CONFIGURATION

The plugin needs to be configured correctly, through an external configuration file in order to

monitor it properly.

NOTE: It is extremely important to consider that the configuration files thought for the plugin in

Page 8

UNIX should be edited and stored with carriage returns type “UNIX” and that if we use carriage

returns type “WINDOWS” the plugin will not work properly.

The configuration file has the following syntax, that we show as example:

mongodb_stats mongostat;check_dbstats;;localhost;27019

The configuration file could have one or several lines, so each line defines the following things:

• Primary operation to execute. (only mongodb_stats as of now)

• Tool used to perform that operation. (should be mongostat, since its location should be

added to the system PATH of the user that executes the agent, otherwise, the absolute path

should be needed as well)

• Operation execution mode. (only check_dbstats mode is supported right now)

• Whether the instance is a sharding controller or not (if it's not the case, leave it blank)

• IP where the MongoDB instance is listening.

• Port where the MongoDB instance is listening.

Each parameter is separated with the “;” character, as we have seen in the previous example.

Authentication support will become available in the next version.

8 INSTALLING

Copy the plugin to the agent plugin directory, or distribute it with file collections. Do the same with

the file conf. The call from the agent will be similar to this, but using the paths where the plugin

Page 9

and conf are.

module_plugin /var/opt/PandoraFMS/etc/pandora/plugins/Pandora_Plugin_MongoDB_v1r1.pl/var/opt/PandoraFMS/etc/pandora/collections/fc_23/zbea-mongodb.conf

Note: the path of configuration file and plugin file could be what you want.

9 CONFIGURATION AND DEPLOYMENT

The use of these scripts with policies is easy. It is based on creating a policy that contains the

plugin (Pandora_Plugin_MongoDB_v1r1.pl) and a configuration file for each agent. So the call to

the policy plugin uses the $HOST and $PORT variables in that file in order to monitor the

instances needed for each server.

Page 10

If the machine is called ilp0x068.tsm.inet, then we should updload a file with the name:

ilp0x068.tsm.inet-mongodb.conf

And use this hostname as the HOST variable inside the configuration file.

The content of the .conf is specific for each system, but all the .conf are copied to all the systems

associated to the policy. However, even by providing a good credential set, only the user that

executes the pandora agent can read these .conf, so this user should also be able to execute the

system commands needed to monitor Mongo (mongostat in this case).

Page 11