Edit the group_vars/all file to reflect the below variables.
-
Use the provided Vagrant file with VirtualBox to create servers to host the cluster and edit your hosts file to include your new servers, e.g.:
10.0.0.101 mongo1 10.0.0.102 mongo2 10.0.0.103 mongo3 10.0.0.104 mongo4 10.0.0.105 mongo4 -
The default directory for storing data is /data, please change it if required. Make sure it has sufficient space: 10G is recommended.
-
The secret file at /roles/mongod_replicaset/secret should be replaced with a custom secret, generated by the following command. See documentation at https://docs.mongodb.org/manual/tutorial/generate-key-file/
openssl rand -base64 741 > secret
The inventory file looks as follows:
[mongo_servers]
mongo1 mongod_port=27017
mongo2 mongod_port=27017
mongo3 mongod_port=27017
mongo4 mongod_port=27017
mongo5 mongod_port=27017
[mongod_primary]
mongo1 mongod_port=27017
[mongod_slaves]
mongo2 mongod_port=27017
mongo3 mongod_port=27017
mongo4 mongod_port=27017
[mongod_arbiters]
mongo5
Build the site with the following command:
ansible-playbook -i hosts 01_create_cluster.yml -u root -k
Once configuration and deployment has completed we can check replication set availability by connecting to individual primary replication set nodes:
mongo --host mongo1 --port 27017
When connected, issue the following commands to query the status of the replication set and you should get a similar output.
mongo_replication:PRIMARY> use admin
switched to db admin
mongo_replication:PRIMARY> db.auth("admin", "123456")
1
mongo_replication:PRIMARY> rs.status()
{
"set" : "mongo_replication",
"date" : ISODate("2015-10-21T19:43:54.932Z"),
"myState" : 1,
"members" : [
{
"_id" : 0,
"name" : "mongo1:27017",
"health" : 1,
"state" : 1,
"stateStr" : "PRIMARY",
"uptime" : 100,
"optime" : Timestamp(1445456545, 1),
"optimeDate" : ISODate("2015-10-21T19:42:25Z"),
"electionTime" : Timestamp(1445456537, 2),
"electionDate" : ISODate("2015-10-21T19:42:17Z"),
"configVersion" : 5,
"self" : true
},
{
"_id" : 1,
"name" : "mongo2:27017",
"health" : 1,
"state" : 2,
"stateStr" : "SECONDARY",
"uptime" : 96,
"optime" : Timestamp(1445456545, 1),
"optimeDate" : ISODate("2015-10-21T19:42:25Z"),
"lastHeartbeat" : ISODate("2015-10-21T19:43:53.716Z"),
"lastHeartbeatRecv" : ISODate("2015-10-21T19:43:54.473Z"),
"pingMs" : 1,
"lastHeartbeatMessage" : "could not find member to sync from",
"configVersion" : 5
},
{
"_id" : 2,
"name" : "mongo3:27017",
"health" : 1,
"state" : 2,
"stateStr" : "SECONDARY",
"uptime" : 94,
"optime" : Timestamp(1445456545, 1),
"optimeDate" : ISODate("2015-10-21T19:42:25Z"),
"lastHeartbeat" : ISODate("2015-10-21T19:43:53.732Z"),
"lastHeartbeatRecv" : ISODate("2015-10-21T19:43:54.906Z"),
"pingMs" : 2,
"lastHeartbeatMessage" : "could not find member to sync from",
"configVersion" : 5
},
{
"_id" : 3,
"name" : "mongo4:27017",
"health" : 1,
"state" : 2,
"stateStr" : "SECONDARY",
"uptime" : 92,
"optime" : Timestamp(1445456545, 1),
"optimeDate" : ISODate("2015-10-21T19:42:25Z"),
"lastHeartbeat" : ISODate("2015-10-21T19:43:53.732Z"),
"lastHeartbeatRecv" : ISODate("2015-10-21T19:43:53.184Z"),
"pingMs" : 3,
"syncingTo" : "mongo3:27017",
"configVersion" : 5
},
{
"_id" : 4,
"name" : "mongo5:27017",
"health" : 1,
"state" : 7,
"stateStr" : "ARBITER",
"uptime" : 89,
"lastHeartbeat" : ISODate("2015-10-21T19:43:53.732Z"),
"lastHeartbeatRecv" : ISODate("2015-10-21T19:43:53.840Z"),
"pingMs" : 0,
"configVersion" : 5
}
],
"ok" : 1
}
To add a new node to the existing MongoDB Cluster, modify the inventory file (/hosts) to add a new server into the mongo_servers section and either the mongod_slaves or mongod_arbiters section.
ansible-playbook -i hosts 02_update_cluster.yml -u root -k
A new server can be created by updating the Vagrant file, and calling "vagrant up", remember to update your /etc/hosts file to include the new server.
###Verification
The newly added node can be easily verified by checking the replication status and seeing the data being copied to the newly added node.
###Serverspec
Verify the servers using serverspec with ansible_spec
$gem install ansible_spec
$rake T
rake serverspec:common
rake serverspec:mongod
$rake serverspec:mongod