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Replica Set

Server IPHost Role
192.168.10.4MongoDB Replica Set Node01
192.168.10.5MongoDB Replica Set Node02
192.168.10.6MongoDB Replica Set Node03

Start Deployment​

MongoDB Replica Set Node01​

  1. Download the MongoDB installation package

    wget https://pdpublic.mingdao.com/private-deployment/offline/common/mongodb-linux-x86_64-3.4.24.tgz

  2. Extract to the installation directory

    tar -zxvf mongodb-linux-x86_64-3.4.24.tgz
    mv mongodb-linux-x86_64-3.4.24 /usr/local/mongodb

  3. Create a MongoDB user

    useradd -M -s /sbin/nologin mongodb

  4. Create data and log directories and grant permissions

    mkdir -p /data/mongodb/ /data/logs/mongodb
    echo '1/3GWm7LjfCX/K2NOhv0evgBWan+KNX' > /data/mongodb/keyfile
    chmod 400 /data/mongodb/keyfile
    chown -R mongodb:mongodb /usr/local/mongodb/ /data/mongodb/ /data/logs/mongodb

  5. Disable Transparent Huge Pages (THP)

    MongoDB may experience performance degradation and memory fragmentation when THP is enabled. It is recommended to disable it via a systemd service before starting MongoDB.

    cat > /etc/systemd/system/disable-thp.service <<\EOF
    [Unit]
    Description=Disable Transparent Huge Pages (THP)
    DefaultDependencies=no
    After=sysinit.target local-fs.target
    Before=mongodb.service
    [Service]
    Type=oneshot
    ExecStart=/bin/sh -c 'echo never > /sys/kernel/mm/transparent_hugepage/enabled'
    ExecStart=/bin/sh -c 'echo never > /sys/kernel/mm/transparent_hugepage/defrag'
    [Install]
    WantedBy=basic.target
    EOF

    systemctl daemon-reload
    systemctl enable disable-thp
    systemctl start disable-thp

  6. Configure the systemd management file

    cat > /etc/systemd/system/mongodb.service <<EOF
    [Unit]
    Description=MongoDB
    After=network-online.target
    Wants=network-online.target
    [Service]
    User=mongodb
    Group=mongodb
    LimitNOFILE=1000000
    LimitNPROC=1000000
    LimitMEMLOCK=infinity
    ExecStart=/usr/local/mongodb/bin/mongod --logpath /data/logs/mongodb/mongodb.log --dbpath /data/mongodb --auth --keyFile /data/mongodb/keyfile --port 27017 --replSet local-mongodb-one
    ExecStop=/usr/bin/kill \$MAINPID
    Restart=on-failure
    RestartSec=5
    TimeoutStopSec=300
    [Install]
    WantedBy=multi-user.target
    EOF

  7. Add to startup

    # Do not use systemctl start mongodb to start the service immediately after installation because the user is not yet created
    systemctl daemon-reload
    systemctl enable mongodb

MongoDB Replica Set Node02​

  1. Download the MongoDB installation package

    wget https://pdpublic.mingdao.com/private-deployment/offline/common/mongodb-linux-x86_64-3.4.24.tgz

  2. Extract to the installation directory

    tar -zxvf mongodb-linux-x86_64-3.4.24.tgz
    mv mongodb-linux-x86_64-3.4.24 /usr/local/mongodb

  3. Create a MongoDB user

    useradd -M -s /sbin/nologin mongodb

  4. Create data and log directories and grant permissions

    mkdir -p /data/mongodb/ /data/logs/mongodb
    echo '1/3GWm7LjfCX/K2NOhv0evgBWan+KNX' > /data/mongodb/keyfile
    chmod 400 /data/mongodb/keyfile
    chown -R mongodb:mongodb /usr/local/mongodb/ /data/mongodb/ /data/logs/mongodb

  5. Disable Transparent Huge Pages (THP)

    MongoDB may experience performance degradation and memory fragmentation when THP is enabled. It is recommended to disable it via a systemd service before starting MongoDB.

    cat > /etc/systemd/system/disable-thp.service <<\EOF
    [Unit]
    Description=Disable Transparent Huge Pages (THP)
    DefaultDependencies=no
    After=sysinit.target local-fs.target
    Before=mongodb.service
    [Service]
    Type=oneshot
    ExecStart=/bin/sh -c 'echo never > /sys/kernel/mm/transparent_hugepage/enabled'
    ExecStart=/bin/sh -c 'echo never > /sys/kernel/mm/transparent_hugepage/defrag'
    [Install]
    WantedBy=basic.target
    EOF

    systemctl daemon-reload
    systemctl enable disable-thp
    systemctl start disable-thp

  6. Configure the systemd management file

    cat > /etc/systemd/system/mongodb.service <<EOF
    [Unit]
    Description=MongoDB
    After=network-online.target
    Wants=network-online.target
    [Service]
    User=mongodb
    Group=mongodb
    LimitNOFILE=1000000
    LimitNPROC=1000000
    LimitMEMLOCK=infinity
    ExecStart=/usr/local/mongodb/bin/mongod --logpath /data/logs/mongodb/mongodb.log --dbpath /data/mongodb --auth --keyFile /data/mongodb/keyfile --port 27017 --replSet local-mongodb-one
    ExecStop=/usr/bin/kill \$MAINPID
    Restart=on-failure
    RestartSec=5
    TimeoutStopSec=300
    [Install]
    WantedBy=multi-user.target
    EOF

  7. Add to startup

    # Do not use systemctl start mongodb to start the service immediately after installation because the user is not yet created
    systemctl daemon-reload
    systemctl enable mongodb

MongoDB Replica Set Node03​

  1. Download the MongoDB installation package

    wget https://pdpublic.mingdao.com/private-deployment/offline/common/mongodb-linux-x86_64-3.4.24.tgz

  2. Extract to the installation directory

    tar -zxvf mongodb-linux-x86_64-3.4.24.tgz
    mv mongodb-linux-x86_64-3.4.24 /usr/local/mongodb

  3. Create a MongoDB user

    useradd -M -s /sbin/nologin mongodb

  4. Create data and log directories and grant permissions

    mkdir -p /data/mongodb/ /data/logs/mongodb
    echo '1/3GWm7LjfCX/K2NOhv0evgBWan+KNX' > /data/mongodb/keyfile
    chmod 400 /data/mongodb/keyfile
    chown -R mongodb:mongodb /usr/local/mongodb/ /data/mongodb/ /data/logs/mongodb

  5. Disable Transparent Huge Pages (THP)

    MongoDB may experience performance degradation and memory fragmentation when THP is enabled. It is recommended to disable it via a systemd service before starting MongoDB.

    cat > /etc/systemd/system/disable-thp.service <<\EOF
    [Unit]
    Description=Disable Transparent Huge Pages (THP)
    DefaultDependencies=no
    After=sysinit.target local-fs.target
    Before=mongodb.service
    [Service]
    Type=oneshot
    ExecStart=/bin/sh -c 'echo never > /sys/kernel/mm/transparent_hugepage/enabled'
    ExecStart=/bin/sh -c 'echo never > /sys/kernel/mm/transparent_hugepage/defrag'
    [Install]
    WantedBy=basic.target
    EOF

    systemctl daemon-reload
    systemctl enable disable-thp
    systemctl start disable-thp

  6. Configure the systemd management file

    cat > /etc/systemd/system/mongodb.service <<EOF
    [Unit]
    Description=MongoDB
    After=network-online.target
    Wants=network-online.target
    [Service]
    User=mongodb
    Group=mongodb
    LimitNOFILE=1000000
    LimitNPROC=1000000
    LimitMEMLOCK=infinity
    ExecStart=/usr/local/mongodb/bin/mongod --logpath /data/logs/mongodb/mongodb.log --dbpath /data/mongodb --auth --keyFile /data/mongodb/keyfile --port 27017 --replSet local-mongodb-one
    ExecStop=/usr/bin/kill \$MAINPID
    Restart=on-failure
    RestartSec=5
    TimeoutStopSec=300
    [Install]
    WantedBy=multi-user.target
    EOF

  7. Add to startup

    # Do not use systemctl start mongodb to start the service immediately after installation because the user is not yet created
    systemctl daemon-reload
    systemctl enable mongodb

Create Database Users​

Run on MongoDB Replica Set Node01.

  1. Temporarily start MongoDB without authentication

    su -c '/usr/local/mongodb/bin/mongod --fork --logpath /data/logs/mongodb/mongodb.log --dbpath /data/mongodb --noauth  --port 27017' -s /bin/bash mongodb

  2. Log in to MongoDB

    Run in the system terminal:

    /usr/local/mongodb/bin/mongo --host 127.0.0.1 --port 27017

    Run the following user creation statements in mongo.

  3. Create the administrator user

    db.getSiblingDB("admin").createUser({
      user: "root",
      pwd: "123456",
      roles: [{role: "root", db: "admin"}]
    });
    • The example password for the root user in the MongoDB admin database is 123456. Replace it with a strong password for your deployment.

  4. Create business database users

    var businessUser = "hap";
    var businessPassword = "123456";
    var databases = [
      "MDLicense",
      "ClientLicense",
      "commonbase",
      "MDAlert",
      "mdapproles",
      "mdapprove",
      "mdapps",
      "mdattachment",
      "mdcalendar",
      "mdcategory",
      "MDChatTop",
      "mdcheck",
      "mddossier",
      "mdemail",
      "mdform",
      "MDGroup",
      "mdgroups",
      "MDHistory",
      "mdIdentification",
      "mdinbox",
      "mdkc",
      "mdmap",
      "mdmobileaddress",
      "MDNotification",
      "mdpost",
      "mdreportdata",
      "mdroles",
      "mdsearch",
      "mdservicedata",
      "mdsms",
      "MDSso",
      "mdtag",
      "mdtransfer",
      "MDUser",
      "mdworkflow",
      "mdworksheet",
      "mdworkweixin",
      "mdwsrows",
      "pushlog",
      "taskcenter",
      "mdintegration",
      "mdactionlog",
      "mdworksheetlog",
      "mdworksheetsearch",
      "mddatapipeline",
      "mdwfplugin",
      "mdpayment",
      "mdwfai",
      "mdopenauth",
      "mdaisearch",
      "MDAgentInfra"
    ];
    for (var i = 0; i < databases.length; i++) {
      var database = databases[i];
      db.getSiblingDB(database).createUser({
        user: businessUser,
        pwd: businessPassword,
        roles: [{role: "readWrite", db: database}]
      });
    }
    • The example password for the hap users in the MongoDB business databases is 123456. Replace it with a strong password for your deployment.
    • If the password contains special characters, use only - or _. Do not use characters such as @ ! # & to avoid compatibility issues.

  5. Exit mongo

    exit();

  6. Stop the temporary MongoDB instance

    Return to the system terminal and run:

    kill $(pgrep -f 'mongod')

Start MongoDB​

Operate on the three servers deployed with MongoDB

systemctl start mongodb

Configure Replica Set​

Operate on the MongoDB Replica Set Node01

  1. Login to MongoDB

    /usr/local/mongodb/bin/mongo -u root -p 123456 --authenticationDatabase admin

  2. Configure the replica set

    rs.initiate({_id: "local-mongodb-one",members:[ {_id : 1, host : "192.168.10.4:27017"},{_id : 2, host : "192.168.10.5:27017"},{_id : 3, host : "192.168.10.6:27017"} ]})
    • Before execution, be sure to modify the IP addresses of the member nodes to the actual server addresses.

  3. Check the replica set status

    rs.status()

    # In the output, typically one node will be PRIMARY, and the other two will be in SECONDARY state.