mohierf/mod-retention-mongodb

Shinken module for saving retention data from schedulers to a mongodb cluster

MongoDB retention module

The high availability allow the Arbiter to send a configuration to a spare scheduler, but a spare scheduler does not have any saved states for hosts and services. It will have to recheck them all. It's better to use a distributed retention module so spares will have all the information they need to start with an accurate picture of the current states and scheduling :)

This is why MongoDB retention module exists ...

MongoDB

MongoDB is a scalable, high-performance, open source NoSQL database written in C++.

Step 1: Install MongoDB:

MongoDB installation procedure from MongoDB installation page:

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv 7F0CEB10
echo "deb http://repo.mongodb.org/apt/debian wheezy/mongodb-org/3.0 main" | sudo tee /etc/apt/sources.list.d/mongodb-org-3.0.list
sudo apt-get update
sudo apt-get install -y mongodb-org

And we install pymongo, the python driver for MongoDB, with pip to avoid distro packages problems:

apt-get remove python-pymongo
pip install pymongo>=3

And finally we start MongoDB :

/etc/init.d/mongodb start

Step 2: configure the module (if needed):

## Module:      retention-mongodb
## Loaded by:   Scheduler
# Retention file to keep state between process restarts.
define module {
   module_name     retention-mongodb
   module_type     mongodb_retention
   uri             mongodb://localhost
   database        shinken

   # Advanced option if you are running a cluster environnement
   #    replica_set
}

Step 3: define a mongodb_retention module in your scheduler configuration file:

define scheduler {
   scheduler_name      scheduler-master ; Just the name

   ...
   modules   retention-mongodb
   ...

}

Step 4: Restart Shinken, and your Scheduler will now save its state between restarts. :)