Mongo Setup Instructions

mongo_setup.md

#Mongo UseCase:

Installing mongodb on 5 machines with the following deamon configurations:

Host	Mongo Role
router.mongo.cw.com	Router(mongos), Application Server, Arbiter (Shard1), Arbiter (Shard2), Config1, Config2, Config3
shard1r1.mongo.cw.com	shard1 replica primary
shard1r2.mongo.cw.com	shard1 replica secondary
shard2r1.mongo.cw.com	shard2 replica primary
shard2r2.mongo.cw.com	shard2 replica secondary

##Install Mongo 2.4 Download and install mongodb on all machines:

cd /opt
curl -o mongodb-2.4.9.tgz http://fastdl.mongodb.org/linux/mongodb-linux-x86_64-2.4.9.tgz
tar xzf mongodb-2.4.9.tgz
rm mongodb*.tgz
ln -s mongodb* mongodb

##Configure ReplicaSet1 and tell it to be shard 1 ####Configure Replica Primary on shard1r1.mongo.cw.com

mkdir -p /data/shard1 /var/log/mongodb
/opt/mongodb/bin/mongod --replSet shard1 --logpath "/var/log/mongodb/shard1.log" --dbpath /data/shard1 --port 27017 --fork --shardsvr --bind_ip shard1r1.mongo.cw.com

####Configure Replica Secondary on shard1r2.mongo.cw.com

mkdir -p /data/shard1 /var/log/mongodb
/opt/mongodb/bin/mongod --replSet shard1 --logpath "/var/log/mongodb/shard1.log" --dbpath /data/shard1 --port 27017 --fork --shardsvr --bind_ip shard1r2.mongo.cw.com

###Configure Replica Arbiter on router.mongo.cw.com

mkdir -p /data/shard1/arbiter /var/log/mongodb
/opt/mongodb/bin/mongod --replSet shard1 --logpath "/var/log/mongodb/arbiter_shard1.log" --dbpath /data/shard1/arbiter --port 47018 --fork --bind_ip router.mongo.cw.com

####Initialize replica set 1 from mongo shell from replica primary 'shard1r1.mongo.cw.com'

Before, doing so wait until all the replicas came up online

/opt/mongodb/bin/mongo --host shard1r1.mongo.cw.com --port 27017 << 'EOF'
rs.initiate()
rs.add('shard1r2.mongo.cw.com:27017')
rs.addArb('router.mongo.cw.com:47018')
EOF

Check if everything is right using : rs.status(), in the output you should be able to see 3 nodes, with status "PRIMARY", "SECONDARY" & "ARBITER" respectively

##Configure ReplicaSet2 for Shard 2 ####Configure Replica Primary on shard2r1.mongo.cw.com

mkdir -p /data/shard2 /var/log/mongodb
/opt/mongodb/bin/mongod --replSet shard2 --logpath "/var/log/mongodb/shard2.log" --dbpath /data/shard2 --port 27017 --fork --shardsvr --bind_ip shard2r1.mongo.cw.com

####Configure Replica Secondary on shard2r2.mongo.cw.com

mkdir -p /data/shard2 /var/log/mongodb
/opt/mongodb/bin/mongod --replSet shard2 --logpath "/var/log/mongodb/shard2.log" --dbpath /data/shard2 --port 27017 --fork --shardsvr --bind_ip shard2r2.mongo.cw.com

###Configure Replica Arbiter on router.mongo.cw.com

mkdir -p /data/shard2/arbiter /var/log/mongodb
/opt/mongodb/bin/mongod --replSet shard2 --logpath "/var/log/mongodb/arbiter_shard2.log" --dbpath /data/shard2/arbiter --port 47019 --fork --bind_ip router.mongo.cw.com

####Initialize replica set 2 from mongo shell from replica primary 'shard2r1.mongo.cw.com'

/opt/mongodb/bin/mongo --host shard2r1.mongo.cw.com --port 27017 << 'EOF'
rs.initiate()
rs.add('shard2r2.mongo.cw.com:27017')
rs.addArb('router.mongo.cw.com:47019')
EOF

##Configure ConfigServer(s) on 'router.mongo.cw.com'

mkdir -p /data/config/config-a /data/config/config-b /data/config/config-c 
/opt/mongodb/bin/mongod --logpath "/var/log/mongodb/cfg-a.log" --dbpath /data/config/config-a --port 37019 --fork --configsvr --bind_ip router.mongo.cw.com
/opt/mongodb/bin/mongod --logpath "/var/log/mongodb/cfg-b.log" --dbpath /data/config/config-b --port 37020 --fork --configsvr --bind_ip router.mongo.cw.com
/opt/mongodb/bin/mongod --logpath "/var/log/mongodb/cfg-c.log" --dbpath /data/config/config-c --port 37021 --fork --configsvr --bind_ip router.mongo.cw.com

##Configure Mongo Router on 'router.mongo.cw.com'

/opt/mongodb/bin/mongos --configdb router.mongo.cw.com:37019,router.mongo.cw.com:37020,router.mongo.cw.com:37021 --fork --logpath "/var/log/mongodb/router.log"

##Enable sharding on the shards ###Connect to mongos instance on router.mongo.cw.com and enable sharding

/opt/mongodb/bin/mongo --port 27017 <<'EOF'
db.adminCommand( { addshard : "shard1/"+"shard1r1.mongo.cw.com:27017" } );
db.adminCommand( { addshard : "shard2/"+"shard2r1.mongo.cw.com:27017" } );
EOF

###Enable sharding for a database 'logs'

/opt/mongodb/bin/mongo --port 27017 <<'EOF'
db.adminCommand({enableSharding: "logs"})
EOF

###Enable sharding for a collection 'logEvents' using hashed key 'record_id'

/opt/mongodb/bin/mongo --port 27017 <<'EOF'
use logs
db.logEvents.ensureIndex( { "record_id": "hashed"} )
sh.shardCollection("logs.logEvents", { "record_id": "hashed" } )
EOF

##Verify Using sh.status() from mongos. Output looks something like this:

--- Sharding Status ---
  sharding version: {
  "_id" : 1,
  "version" : 3,
  "minCompatibleVersion" : 3,
  "currentVersion" : 4,
  "clusterId" : ObjectId("52884c78701249e73d126128")
}
  shards:
  {  "_id" : "shard1",  "host" : "shard1/ip-10-168-129-36.us-west-1.compute.internal:27017,ip-10-169-41-183:27017" }
  {  "_id" : "shard2",  "host" : "shard2/ip-10-168-10-49.us-west-1.compute.internal:27017,ip-10-168-98-40:27017" }
  databases:
  {  "_id" : "admin",  "partitioned" : false,  "primary" : "config" }
  {  "_id" : "logs",  "partitioned" : true,  "primary" : "shard2" }
    logs.logEvents
      shard key: { "record_id" : "hashed" }
      chunks:
        shard2  2
        shard1  2
      { "record_id" : { "$minKey" : 1 } } -->> { "record_id" : NumberLong("-4611686018427387902") } on : shard2 Timestamp(2, 2)
      { "record_id" : NumberLong("-4611686018427387902") } -->> { "record_id" : NumberLong(0) } on : shard2 Timestamp(2, 3)
      { "record_id" : NumberLong(0) } -->> { "record_id" : NumberLong("4611686018427387902") } on : shard1 Timestamp(2, 4)
      { "record_id" : NumberLong("4611686018427387902") } -->> { "record_id" : { "$maxKey" : 1 } } on : shard1 Timestamp(2, 5)