Procedure 12.1. Configuring the MongoDB Back End and Creating the Telemetry Database

1. Optionally configure mongod to run with the --smallfiles parameter. Open the /etc/sysconfig/mongod file in a text editor, and add the following line:

   OPTIONS="--smallfiles /etc/mongodb.conf"

   MongoDB uses the parameters specified in the OPTIONS section when mongod launches.
2. Start the MongoDB service:

   # systemctl start mongod.service

3. If the database must be accessed from a server other than its local host, open the /etc/mongod.conf file in a text editor, and update the bind_ip with the IP address of your MongoDB server:

   bind_ip = MONGOHOST

4. Open the /etc/sysconfig/iptables file in a text editor and add an INPUT rule allowing TCP traffic on port 27017. The new rule must appear before any INPUT rules that REJECT traffic:

   -A INPUT -p tcp -m multiport --dports 27017 -j ACCEPT

5. Restart the iptables service to ensure that the change takes effect:

   # systemctl restart iptables.service

6. Create a database for the Telemetry service:

   # mongo --host MONGOHOST --eval '
      db = db.getSiblingDB("ceilometer");
      db.addUser({user: "ceilometer",
   	   pwd: "MONGOPASS",
   	   roles: [ "readWrite", "dbAdmin" ]})'

   This also creates a database user named ceilometer. Replace MONGOHOST with the IP address or host name of the server hosting the MongoDB database. Replace MONGOPASS with a password for the ceilometer user.