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Naresh Maharaj
Naresh Maharaj

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MongoDB Sharding - Single Node Macbook - Quick Setup

MongoDB Sharding - Single Node Macbook - Quick Setup

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There are times when I need to quickly set up a shard, or even a MongoDB cluster with 2 or 3 shards. This guide makes it simple and configurable to do so with a single command. No Docker is involved—just plain old MongoDB, specifically version 8, which is the latest at the time of writing.

Git repo here in case you want to skip reading this:
https://github.com/nareshmaharaj-consultant/mongodb-sharding-bash

Overview

Let's begin by installing all the necessary binaries.

  • mongosh: Download the MongoDB shell, as we'll need this multiple times throughout the setup.
  • mongod: Grab the latest MongoDB server, required for each instance.

After downloading, unzip the contents and move the bin folder contents to your system’s environment paths.

You should now be able to run the following commands to verify the versions of both.

mongosh --version
2.3.1

mongod --version
db version v8.0.0
Build Info: {
    "version": "8.0.0",
    "gitVersion": "d7cd03b239ac39a3c7d63f7145e91aca36f93db6",
    "modules": [
        "enterprise"
    ],
    "allocator": "system",
    "environment": {
        "distarch": "x86_64",
        "target_arch": "x86_64"
    }
}
mongos --version
mongos version v8.0.0
Build Info: {
    "version": "8.0.0",
    "gitVersion": "d7cd03b239ac39a3c7d63f7145e91aca36f93db6",
    "modules": [
        "enterprise"
    ],
    "allocator": "system",
    "environment": {
        "distarch": "x86_64",
        "target_arch": "x86_64"
    }
}
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Once everything is confirmed, we're good to go. We'll follow the sequence below:

  • Replica Sets: First, we'll create a simple replica set and then tear it down.
  • Shards: Set up a sharded cluster with 2 shards.
  • Data: Insert some sample data.
  • Collections: Shard the collection.
  • Config Shard: Convert the config server(s) into a data shard.
  • Wrap up: What’s next?

Replica Set

Start by creating a file named mongo-replicaset-create to set up the replica set.

NAME=$1
PORT=$2
DIR=~/data/$NAME
NODES=$3
USAGE="\nUsage:  mongo-replicaset-create {name} {port} {numNodes} { Optional:[ --shardsvr, --configsvr ] }\nSet env variable \$HOST for all nodes to use this domain name."
SLEEPTIME=8
CONFIGSVR=""
SHARDSVR=""
GIVEN_HOSTNAME=localhost

if [ -z "$HOST" ]
then
      echo "\$HOST not set using localhost"
else
      GIVEN_HOSTNAME=$HOST
fi

if [ "$1" == "-h" ]; then
  echo -e $USAGE
  exit 0
fi

if [ -z "$1" ]
  then
    echo -e "No NAME argument supplied $USAGE"
    exit 0
fi

if [ -z "$2" ]
  then
    echo -e "No PORT argument supplied $USAGE"
    exit 0
fi

if [ -z "$3" ]
  then
    echo -e "Number of NODES  argument supplied $USAGE"
    exit 0
fi

# idiomatic parameter and option handling in sh
while test $# -gt 0
do
    case "$4" in
        --shardsvr) echo "Using option --shardsvr"
        SHARDSVR="--shardsvr"
            ;;
        --configsvr) echo "Using option --configsvr"
        CONFIGSVR="--configsvr"
            ;;
        --*) echo "bad option $1"
            ;;
    esac
    shift
done

rm -fr $DIR
mkdir -p $DIR

COUNTER=0
  until [  $COUNTER -ge $NODES ]; do
    LOC=$DIR/$COUNTER
    mkdir -p $LOC
    PC=$(($PORT+$COUNTER))
    echo "[ ++ Executing:  mongod --port $PC --fork --dbpath $LOC --logpath $LOC/log.out -replSet $NAME $CONFIGSVR $SHARDSVR ]"
    mongod --port $PC --fork --bind_ip localhost,$GIVEN_HOSTNAME --dbpath $LOC --logpath $LOC/log.out --replSet $NAME $CONFIGSVR $SHARDSVR
    let COUNTER+=1
  done

echo "Sleeping for $SLEEPTIME seconds"
sleep $SLEEPTIME

echo "[ ++ Executing:  mongosh --port $PORT -eval \"rs.initiate()\" ]"
mongosh --port $PORT -eval "rs.initiate()"
sleep $SLEEPTIME

COUNTER=1
  until [  $COUNTER -ge $NODES ]; do
    PC=$(($PORT+$COUNTER))
    if [ $COUNTER -gt 6 ]; then
    echo "[ ++ Executing: mongosh --port $PORT -eval \"rs.add({host: '$GIVEN_HOSTNAME:$PC', priority:0, votes:0})\" ]"
    mongosh --port $PORT -eval "rs.add({host: '$GIVEN_HOSTNAME:$PC', priority:0, votes:0})"
    else
        echo "[ ++ Executing:  mongosh --port $PORT -eval \"rs.add('$GIVEN_HOSTNAME:$PC')\" ]"
        mongosh --port $PORT -eval "rs.add('$GIVEN_HOSTNAME:$PC')"
    fi
    let COUNTER+=1
  done

sleep $SLEEPTIME
mongosh --port $PORT -eval "rs.status()"
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Create the replica set and capture the stdout if you want to inspect the output later. It makes sense to set the HOST variable so that it can be used as a Fully Qualified Domain Name (FQDN) during the creation process.

# Set the host
export HOST=`hostname`

# Check we set it correctly
env | grep HOST
HOST=nmaharaj-MBP-MMD6T.local
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Run the script

mongo-replicaset-create myrs 27017 3
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Here is the result and output

[ ++ Executing:  mongod --port 27017 --fork --dbpath /Users/nareshmaharaj/data/myrs/0 --logpath /Users/nareshmaharaj/data/myrs/0/log.out -replSet myrs   ]
about to fork child process, waiting until server is ready for connections.
forked process: 43633
child process started successfully, parent exiting
[ ++ Executing:  mongod --port 27018 --fork --dbpath /Users/nareshmaharaj/data/myrs/1 --logpath /Users/nareshmaharaj/data/myrs/1/log.out -replSet myrs   ]
about to fork child process, waiting until server is ready for connections.
forked process: 43664
child process started successfully, parent exiting
[ ++ Executing:  mongod --port 27019 --fork --dbpath /Users/nareshmaharaj/data/myrs/2 --logpath /Users/nareshmaharaj/data/myrs/2/log.out -replSet myrs   ]
about to fork child process, waiting until server is ready for connections.
forked process: 43689
child process started successfully, parent exiting
Sleeping for 8 seconds
[ ++ Executing:  mongosh --port 27017 -eval "rs.initiate()" ]
{
  info2: 'no configuration specified. Using a default configuration for the set',
  me: 'nmaharaj-MBP-MMD6T.local:27017',
  ok: 1,
  '$clusterTime': {
    clusterTime: Timestamp({ t: 1728146621, i: 1 }),
    signature: {
      hash: Binary.createFromBase64('AAAAAAAAAAAAAAAAAAAAAAAAAAA=', 0),
      keyId: Long('0')
    }
  },
  operationTime: Timestamp({ t: 1728146621, i: 1 })
}
[ ++ Executing:  mongosh --port 27017 -eval "rs.add('nmaharaj-MBP-MMD6T.local:27018')" ]
{
  ok: 1,
  '$clusterTime': {
    clusterTime: Timestamp({ t: 1728146631, i: 1 }),
    signature: {
      hash: Binary.createFromBase64('AAAAAAAAAAAAAAAAAAAAAAAAAAA=', 0),
      keyId: Long('0')
    }
  },
  operationTime: Timestamp({ t: 1728146631, i: 1 })
}
[ ++ Executing:  mongosh --port 27017 -eval "rs.add('nmaharaj-MBP-MMD6T.local:27019')" ]
{
  ok: 1,
  '$clusterTime': {
    clusterTime: Timestamp({ t: 1728146633, i: 1 }),
    signature: {
      hash: Binary.createFromBase64('AAAAAAAAAAAAAAAAAAAAAAAAAAA=', 0),
      keyId: Long('0')
    }
  },
  operationTime: Timestamp({ t: 1728146633, i: 1 })
}
{
  set: 'myrs',
  date: ISODate('2024-10-05T16:44:02.989Z'),
  myState: 1,
  term: Long('1'),
  syncSourceHost: '',
  syncSourceId: -1,
  heartbeatIntervalMillis: Long('2000'),
  majorityVoteCount: 2,
  writeMajorityCount: 2,
  votingMembersCount: 3,
  writableVotingMembersCount: 3,
  optimes: {
    lastCommittedOpTime: { ts: Timestamp({ t: 1728146641, i: 1 }), t: Long('1') },
    lastCommittedWallTime: ISODate('2024-10-05T16:44:01.930Z'),
    readConcernMajorityOpTime: { ts: Timestamp({ t: 1728146641, i: 1 }), t: Long('1') },
    appliedOpTime: { ts: Timestamp({ t: 1728146641, i: 1 }), t: Long('1') },
    durableOpTime: { ts: Timestamp({ t: 1728146641, i: 1 }), t: Long('1') },
    writtenOpTime: { ts: Timestamp({ t: 1728146641, i: 1 }), t: Long('1') },
    lastAppliedWallTime: ISODate('2024-10-05T16:44:01.930Z'),
    lastDurableWallTime: ISODate('2024-10-05T16:44:01.930Z'),
    lastWrittenWallTime: ISODate('2024-10-05T16:44:01.930Z')
  },
  lastStableRecoveryTimestamp: Timestamp({ t: 1728146621, i: 1 }),
  electionCandidateMetrics: {
    lastElectionReason: 'electionTimeout',
    lastElectionDate: ISODate('2024-10-05T16:43:42.053Z'),
    electionTerm: Long('1'),
    lastCommittedOpTimeAtElection: { ts: Timestamp({ t: 1728146621, i: 1 }), t: Long('-1') },
    lastSeenWrittenOpTimeAtElection: { ts: Timestamp({ t: 1728146621, i: 1 }), t: Long('-1') },
    lastSeenOpTimeAtElection: { ts: Timestamp({ t: 1728146621, i: 1 }), t: Long('-1') },
    numVotesNeeded: 1,
    priorityAtElection: 1,
    electionTimeoutMillis: Long('10000'),
    newTermStartDate: ISODate('2024-10-05T16:43:42.465Z'),
    wMajorityWriteAvailabilityDate: ISODate('2024-10-05T16:43:42.735Z')
  },
  members: [
    {
      _id: 0,
      name: 'nmaharaj-MBP-MMD6T.local:27017',
      health: 1,
      state: 1,
      stateStr: 'PRIMARY',
      uptime: 40,
      optime: { ts: Timestamp({ t: 1728146641, i: 1 }), t: Long('1') },
      optimeDate: ISODate('2024-10-05T16:44:01.000Z'),
      optimeWritten: { ts: Timestamp({ t: 1728146641, i: 1 }), t: Long('1') },
      optimeWrittenDate: ISODate('2024-10-05T16:44:01.000Z'),
      lastAppliedWallTime: ISODate('2024-10-05T16:44:01.930Z'),
      lastDurableWallTime: ISODate('2024-10-05T16:44:01.930Z'),
      lastWrittenWallTime: ISODate('2024-10-05T16:44:01.930Z'),
      syncSourceHost: '',
      syncSourceId: -1,
      infoMessage: 'Could not find member to sync from',
      electionTime: Timestamp({ t: 1728146622, i: 1 }),
      electionDate: ISODate('2024-10-05T16:43:42.000Z'),
      configVersion: 5,
      configTerm: 1,
      self: true,
      lastHeartbeatMessage: ''
    },
    {
      _id: 1,
      name: 'nmaharaj-MBP-MMD6T.local:27018',
      health: 1,
      state: 2,
      stateStr: 'SECONDARY',
      uptime: 11,
      optime: { ts: Timestamp({ t: 1728146641, i: 1 }), t: Long('1') },
      optimeDurable: { ts: Timestamp({ t: 1728146641, i: 1 }), t: Long('1') },
      optimeWritten: { ts: Timestamp({ t: 1728146641, i: 1 }), t: Long('1') },
      optimeDate: ISODate('2024-10-05T16:44:01.000Z'),
      optimeDurableDate: ISODate('2024-10-05T16:44:01.000Z'),
      optimeWrittenDate: ISODate('2024-10-05T16:44:01.000Z'),
      lastAppliedWallTime: ISODate('2024-10-05T16:44:01.930Z'),
      lastDurableWallTime: ISODate('2024-10-05T16:44:01.930Z'),
      lastWrittenWallTime: ISODate('2024-10-05T16:44:01.930Z'),
      lastHeartbeat: ISODate('2024-10-05T16:44:02.075Z'),
      lastHeartbeatRecv: ISODate('2024-10-05T16:44:02.075Z'),
      pingMs: Long('9'),
      lastHeartbeatMessage: '',
      syncSourceHost: 'nmaharaj-MBP-MMD6T.local:27017',
      syncSourceId: 0,
      infoMessage: '',
      configVersion: 5,
      configTerm: 1
    },
    {
      _id: 2,
      name: 'nmaharaj-MBP-MMD6T.local:27019',
      health: 1,
      state: 2,
      stateStr: 'SECONDARY',
      uptime: 9,
      optime: { ts: Timestamp({ t: 1728146637, i: 1 }), t: Long('1') },
      optimeDurable: { ts: Timestamp({ t: 1728146637, i: 1 }), t: Long('1') },
      optimeWritten: { ts: Timestamp({ t: 1728146637, i: 1 }), t: Long('1') },
      optimeDate: ISODate('2024-10-05T16:43:57.000Z'),
      optimeDurableDate: ISODate('2024-10-05T16:43:57.000Z'),
      optimeWrittenDate: ISODate('2024-10-05T16:43:57.000Z'),
      lastAppliedWallTime: ISODate('2024-10-05T16:44:01.930Z'),
      lastDurableWallTime: ISODate('2024-10-05T16:44:01.930Z'),
      lastWrittenWallTime: ISODate('2024-10-05T16:44:01.930Z'),
      lastHeartbeat: ISODate('2024-10-05T16:44:02.078Z'),
      lastHeartbeatRecv: ISODate('2024-10-05T16:44:02.579Z'),
      pingMs: Long('3'),
      lastHeartbeatMessage: '',
      syncSourceHost: '',
      syncSourceId: -1,
      infoMessage: '',
      configVersion: 5,
      configTerm: 1
    }
  ],
  ok: 1,
  '$clusterTime': {
    clusterTime: Timestamp({ t: 1728146641, i: 1 }),
    signature: {
      hash: Binary.createFromBase64('AAAAAAAAAAAAAAAAAAAAAAAAAAA=', 0),
      keyId: Long('0')
    }
  },
  operationTime: Timestamp({ t: 1728146641, i: 1 })
}
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All the commands that were run are shown with the prefix: ++ Executing: ...

Next, log in to the host.

mongosh nmaharaj-MBP-MMD6T.local:27019
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Now, tear everything down by running the following commands. Make sure to wait for all processes to be completely removed.

kill `ps -elf | grep mongo | awk '{print $2}' | tr '\n' ' ' | awk '{$1=$1};1'` > /dev/null 2>&1
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Sharded Cluster

To create a sharded cluster with a config server replicaset and a mongos router, create a file named mongo-shard-create with the following contents.

PORT=$1
SHARDS=$2
LISTNAMES=$3
DIR=~/data/mongos/
USAGE="Usage:  mongo-shard-create {port} {numShards} { shardName1,shardName2,..}"
GIVEN_HOSTNAME=localhost
SLEEPTIME=1

if [ -z "$HOST" ]
then
      echo "\$HOST is empty but is optional - will use localhost"
else
      GIVEN_HOSTNAME=$HOST
fi


if [ -z "$1" ]
  then
    echo "No PORT argument supplied - $USAGE"
    exit 0
fi

if [ -z "$2" ]
  then
    echo "Number of Shards required - $USAGE"
    exit 0
fi

if [ -z "$3" ]
  then
    echo "Name of each shard csv required - $USAGE"
    exit 0
fi

# Split the names for each RS
rs_name_arr=($(echo "$3" | sed "s/ //g" | tr ',' '\n'))
count=${#rs_name_arr[@]}
if [ $count -lt $SHARDS ]
  then
    echo "Shard names(s) count does not match number of Shards required - $USAGE"
    exit 0
fi

echo "##########################################################################################################"
echo "######################################### Creating Replica Sets ##########################################"
echo "##########################################################################################################"
COUNTER=1
  until [  $COUNTER -gt $SHARDS ]; do
  name=${rs_name_arr[$COUNTER-1]}
    PC=$(($PORT+1000*$COUNTER))
    #PC=$(($PORT+17+1000*$COUNTER))
    mongo-replicaset-create $name $PC 3 --shardsvr
    let COUNTER+=1
  done

echo "##########################################################################################################"
echo "######################################### Creating Config Sets ###########################################"
echo "##########################################################################################################"
# Config Servers
#PC=$(($PORT+17+$SHARDS*1000+1000))
PC=$(($PORT+$SHARDS*1000+1000))
mongo-replicaset-create csrs $PC 3 --configsvr

echo " *** Adding user: 'admin', pwd: 'password' to Config Server - please change password *** "
CSRS_HOSTS="csrs/$GIVEN_HOSTNAME:$PC,$GIVEN_HOSTNAME:$(($PC+1)),$GIVEN_HOSTNAME:$(($PC+2))"
mongosh --host $CSRS_HOSTS --eval "db.getSiblingDB('admin').createUser({ user: 'admin', pwd: 'password', roles: [ {role: 'root', db: 'admin'} ] })"


echo "##########################################################################################################"
echo "######################################### Creating mongos #### ###########################################"
echo "##########################################################################################################"
LOG_DIR_MONGOS=~/data/mongos/
mkdir -p $LOG_DIR_MONGOS
#echo "[ ++ Executing:  mongos --port $(($PORT+17)) --bind_ip_all --fork --logpath $LOG_DIR_MONGOS/mongos.log --configdb $CSRS_HOSTS ]"
#mongos --port $(($PORT+17)) --bind_ip_all --fork --logpath $LOG_DIR_MONGOS/mongos.log --configdb $CSRS_HOSTS
echo "[ ++ Executing:  mongos --port $(($PORT)) --bind_ip_all --fork --logpath $LOG_DIR_MONGOS/mongos.log --configdb $CSRS_HOSTS ]"
mongos --port $(($PORT)) --bind_ip_all --fork --logpath $LOG_DIR_MONGOS/mongos.log --configdb $CSRS_HOSTS

COUNTER=1
  until [  $COUNTER -gt $SHARDS ]; do
  name=${rs_name_arr[$COUNTER-1]}
    #PC=$(($PORT+17+1000*$COUNTER))
    #echo "[ ++ Executing: mongosh --port $(($PORT+17)) --eval \"sh.addShard('$name/$GIVEN_HOSTNAME:$PC')\" ]"
    #mongosh --port $(($PORT+17)) --eval "sh.addShard('$name/$GIVEN_HOSTNAME:$PC')"
    PC=$(($PORT+1000*$COUNTER))
    echo "[ ++ Executing: mongosh --port $(($PORT)) --eval \"sh.addShard('$name/$GIVEN_HOSTNAME:$PC')\" ]"
    mongosh --port $(($PORT)) --eval "sh.addShard('$name/$GIVEN_HOSTNAME:$PC')"
    let COUNTER+=1
  done

sleep 5
#mongosh --port $(($PORT+17)) --eval "sh.status()"
mongosh --port $(($PORT)) --eval "sh.status()"
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Run the following command to create a MongoDB sharded cluster with 2 shards.

mongo-shard-create 27017 2 sh1,sh2 | tee ~/out.log
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Here is the output; however, we have omitted most of it due to its large size. We have included all the executed commands and the last part of the stdout.

# commands executed
cat ~/out.log | grep -e Exec -e pass
[ ++ Executing:  mongod --port 28017 --fork --dbpath /Users/nareshmaharaj/data/sh1/0 --logpath /Users/nareshmaharaj/data/sh1/0/log.out -replSet sh1  --shardsvr ]
[ ++ Executing:  mongod --port 28018 --fork --dbpath /Users/nareshmaharaj/data/sh1/1 --logpath /Users/nareshmaharaj/data/sh1/1/log.out -replSet sh1  --shardsvr ]
[ ++ Executing:  mongod --port 28019 --fork --dbpath /Users/nareshmaharaj/data/sh1/2 --logpath /Users/nareshmaharaj/data/sh1/2/log.out -replSet sh1  --shardsvr ]
[ ++ Executing:  mongosh --port 28017 -eval "rs.initiate()" ]
[ ++ Executing:  mongosh --port 28017 -eval "rs.add('nmaharaj-MBP-MMD6T.local:28018')" ]
[ ++ Executing:  mongosh --port 28017 -eval "rs.add('nmaharaj-MBP-MMD6T.local:28019')" ]
[ ++ Executing:  mongod --port 29017 --fork --dbpath /Users/nareshmaharaj/data/sh2/0 --logpath /Users/nareshmaharaj/data/sh2/0/log.out -replSet sh2  --shardsvr ]
[ ++ Executing:  mongod --port 29018 --fork --dbpath /Users/nareshmaharaj/data/sh2/1 --logpath /Users/nareshmaharaj/data/sh2/1/log.out -replSet sh2  --shardsvr ]
[ ++ Executing:  mongod --port 29019 --fork --dbpath /Users/nareshmaharaj/data/sh2/2 --logpath /Users/nareshmaharaj/data/sh2/2/log.out -replSet sh2  --shardsvr ]
[ ++ Executing:  mongosh --port 29017 -eval "rs.initiate()" ]
[ ++ Executing:  mongosh --port 29017 -eval "rs.add('nmaharaj-MBP-MMD6T.local:29018')" ]
[ ++ Executing:  mongosh --port 29017 -eval "rs.add('nmaharaj-MBP-MMD6T.local:29019')" ]
[ ++ Executing:  mongod --port 30017 --fork --dbpath /Users/nareshmaharaj/data/csrs/0 --logpath /Users/nareshmaharaj/data/csrs/0/log.out -replSet csrs --configsvr  ]
[ ++ Executing:  mongod --port 30018 --fork --dbpath /Users/nareshmaharaj/data/csrs/1 --logpath /Users/nareshmaharaj/data/csrs/1/log.out -replSet csrs --configsvr  ]
[ ++ Executing:  mongod --port 30019 --fork --dbpath /Users/nareshmaharaj/data/csrs/2 --logpath /Users/nareshmaharaj/data/csrs/2/log.out -replSet csrs --configsvr  ]
[ ++ Executing:  mongosh --port 30017 -eval "rs.initiate()" ]
[ ++ Executing:  mongosh --port 30017 -eval "rs.add('nmaharaj-MBP-MMD6T.local:30018')" ]
[ ++ Executing:  mongosh --port 30017 -eval "rs.add('nmaharaj-MBP-MMD6T.local:30019')" ]
 *** Adding user: 'admin', pwd: 'password' to Config Server - please change password ***
[ ++ Executing:  mongos --port 27017 --bind_ip_all --fork --logpath /Users/nareshmaharaj/data/mongos//mongos.log --configdb csrs/nmaharaj-MBP-MMD6T.local:30017,nmaharaj-MBP-MMD6T.local:30018,nmaharaj-MBP-MMD6T.local:30019 ]
[ ++ Executing: mongosh --port 27017 --eval "sh.addShard('sh1/nmaharaj-MBP-MMD6T.local:28017')" ]
[ ++ Executing: mongosh --port 27017 --eval "sh.addShard('sh2/nmaharaj-MBP-MMD6T.local:29017')" ]

# stdout
...
##########################################################################################################
######################################### Creating mongos #### ###########################################
##########################################################################################################
[ ++ Executing:  mongos --port 27017 --bind_ip_all --fork --logpath /Users/nareshmaharaj/data/mongos//mongos.log --configdb csrs/nmaharaj-MBP-MMD6T.local:30017,nmaharaj-MBP-MMD6T.local:30018,nmaharaj-MBP-MMD6T.local:30019 ]
about to fork child process, waiting until server is ready for connections.
forked process: 51366
child process started successfully, parent exiting
[ ++ Executing: mongosh --port 27017 --eval "sh.addShard('sh1/nmaharaj-MBP-MMD6T.local:28017')" ]
{
  shardAdded: 'sh1',
  ok: 1,
  '$clusterTime': {
    clusterTime: Timestamp({ t: 1728147532, i: 6 }),
    signature: {
      hash: Binary.createFromBase64('AAAAAAAAAAAAAAAAAAAAAAAAAAA=', 0),
      keyId: Long('0')
    }
  },
  operationTime: Timestamp({ t: 1728147532, i: 6 })
}
[ ++ Executing: mongosh --port 27017 --eval "sh.addShard('sh2/nmaharaj-MBP-MMD6T.local:29017')" ]
{
  shardAdded: 'sh2',
  ok: 1,
  '$clusterTime': {
    clusterTime: Timestamp({ t: 1728147535, i: 16 }),
    signature: {
      hash: Binary.createFromBase64('AAAAAAAAAAAAAAAAAAAAAAAAAAA=', 0),
      keyId: Long('0')
    }
  },
  operationTime: Timestamp({ t: 1728147535, i: 10 })
}
shardingVersion
{ _id: 1, clusterId: ObjectId('670170310cdeaa5de24f0045') }
---
shards
[
  {
    _id: 'sh1',
    host: 'sh1/nmaharaj-MBP-MMD6T.local:28017,nmaharaj-MBP-MMD6T.local:28018,nmaharaj-MBP-MMD6T.local:28019',
    state: 1,
    topologyTime: Timestamp({ t: 1728147531, i: 6 }),
    replSetConfigVersion: Long('-1')
  },
  {
    _id: 'sh2',
    host: 'sh2/nmaharaj-MBP-MMD6T.local:29017,nmaharaj-MBP-MMD6T.local:29018,nmaharaj-MBP-MMD6T.local:29019',
    state: 1,
    topologyTime: Timestamp({ t: 1728147535, i: 1 }),
    replSetConfigVersion: Long('-1')
  }
]
---
active mongoses
[ { '8.0.0': 1 } ]
---
autosplit
{ 'Currently enabled': 'yes' }
---
balancer
{
  'Currently enabled': 'yes',
  'Currently running': 'no',
  'Failed balancer rounds in last 5 attempts': 0,
  'Migration Results for the last 24 hours': 'No recent migrations'
}
---
databases
[
  {
    database: { _id: 'config', primary: 'config', partitioned: true },
    collections: {}
  }
]
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As you can see, we now have a fully configured sharded cluster, and it only takes about a minute to set up.

Log into mongos using mongosh on port 27017 and check the status of the shards.

mongosh --port 27017 --eval "sh.status()"
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Note that there are only 2 shards. As of version 8.0, you can transition the config servers to data shards. Let's see how this is done.

Log in to mongos using mongosh on port 27017.

mongosh --port 27017"
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Run the following command:

db.adminCommand({transitionFromDedicatedConfigServer:1})
{
  ok: 1,
  '$clusterTime': {
    clusterTime: Timestamp({ t: 1728148222, i: 12 }),
    signature: {
      hash: Binary.createFromBase64('AAAAAAAAAAAAAAAAAAAAAAAAAAA=', 0),
      keyId: Long('0')
    }
  },
  operationTime: Timestamp({ t: 1728148222, i: 12 })
}
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Now, check to see how many data shards are present.

mongosh --port 27017 --eval "sh.status()"
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You should now see all 3

shards
[
  {
    _id: 'config',
    host: 'csrs/nmaharaj-MBP-MMD6T.local:30017,nmaharaj-MBP-MMD6T.local:30018,nmaharaj-MBP-MMD6T.local:30019',
    state: 1,
    topologyTime: Timestamp({ t: 1728148222, i: 3 }),
    replSetConfigVersion: Long('-1')
  },
  {
    _id: 'sh1',
    host: 'sh1/nmaharaj-MBP-MMD6T.local:28017,nmaharaj-MBP-MMD6T.local:28018,nmaharaj-MBP-MMD6T.local:28019',
    state: 1,
    topologyTime: Timestamp({ t: 1728147531, i: 6 }),
    replSetConfigVersion: Long('-1')
  },
  {
    _id: 'sh2',
    host: 'sh2/nmaharaj-MBP-MMD6T.local:29017,nmaharaj-MBP-MMD6T.local:29018,nmaharaj-MBP-MMD6T.local:29019',
    state: 1,
    topologyTime: Timestamp({ t: 1728147535, i: 1 }),
    replSetConfigVersion: Long('-1')
  }
]
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