Galera (cluster)

Deploy Galera, a synchronous multi-master replication solution for relational databases such as MariaDB and MySQL that maintains data consistency across multiple servers.

📘

Cluster deployment

The app is deployed with three Linode instances to create a highly available MariaDB Galera cluster, each with the plan type and size you select.

Each of these Linode instances will appear on your invoice as separate items. To deploy MariaDB on a single instance, see the MySQL/MariaDB guide.

1. Deploy Galera cluster

 Estimated deployment time: 5–10 minutes

Base distribution and plan

• Supported distribution: Ubuntu 24.04 LTS
• Recommended plan: Depends on the size of your MySQL database and the amount of traffic you expect.

Configuration options

StackScript ID: 1088136

Use API, CLI, or Terraform

curl --location 'https://api.linode.com/v4/linode/instances' \
    --header 'Content-Type: application/json' \
    --header 'Accept: application/json' \
    --header 'Authorization: Bearer abc123def456hij789klm' \
    --data-raw '{
        "region": "us-east",
        "type": "g6-standard-2",
        "image": "linode/ubuntu24.04",
        "label": "my-galera-cluster-one-click-app",
        "root_pass": "@C0mpl3x#P@ssw0rd",
        "stackscript_id": 1088136,
        "stackscript_data": {
            "cluster_name":"my-cluster",
            "token_password":"abc123def456hij789klm",
            "add_ssh_keys":"no",
            "country_name":"US",
            "state_or_province_name":"Massachusetts",
            "locality_name": "Cambridge",
            "organization_name":"Akamai Technologies",
            "email_address":"jsmith@example.com"
        }
    }'

linode-cli linodes create \
    --region us-east \
    --type g6-standard-2 \
    --label my-galera-cluster-one-click-app \
    --image linode/ubuntu24.04 \
    --root_pass @C0mpl3x#P@ssw0rd \
    --stackscript_id 1088136 \
    --stackscript_data '{"cluster_name":"my-cluster", "token_password":"abc123def456hij789klm", "add_ssh_keys": "no", "country_name":"US", "state_or_province_name":"Massachusetts", "locality_name":"Cambridge", "organization_name": "Akamai Technologies", "email_address":"jsmith@example.com"}'

resource "linode_instance" "my-linode" {
    region         = "us-east"
    type           = "g6-standard-2"
    label          = "my-galera-cluster-one-click-app"
    image          = "linode/ubuntu24.04"
    root_pass      = "@C0mpl3x#P@ssw0rd"
    stackscript_id = 1088136
    stackscript_data = {
        "cluster_name"           = "my-cluster"
        "token_password"         = "abc123def456hij789klm"
        "add_ssh_keys"           = "no"
        "country_name"           = "US"
        "state_or_province_name" = "Massachusetts"
        "locality_name"          = "Cambridge"
        "organization_name"      = "Akamai Technologies"
        "email_address"          = "jsmith@example.com"
    }
}

2. Access MySQL/MariaDB

The standard tool for interacting with MariaDB is the mysql client, which installs with the mysql-server package. The MariaDB client is used through a terminal.

Log in as root

1. Log in to MySQL as the root user by running the sudo mysql -u root -p command.

2. When prompted, enter the MySQL root password you set when launching the Quick Deploy App. Then, you'll see a welcome header and the MySQL prompt like this one, MariaDB [(none)]>.

3. Generate a list of commands for the MySQL prompt by entering \h.

   Output

   List of all MySQL commands:
   Note that all text commands must be first on line and end with ';'
   ?         (\?) Synonym for `help'.
   clear     (\c) Clear command.
   connect   (\r) Reconnect to the server. Optional arguments are db and host.
   delimiter (\d) Set statement delimiter. NOTE: Takes the rest of the line as new delimiter.
   edit      (\e) Edit command with $EDITOR.
   ego       (\G) Send command to mysql server, display result vertically.
   exit      (\q) Exit mysql. Same as quit.
   go        (\g) Send command to mysql server.
   help      (\h) Display this help.
   nopager   (\n) Disable pager, print to stdout.
   notee     (\t) Don't write into outfile.
   pager     (\P) Set PAGER [to_pager]. Print the query results via PAGER.
   print     (\p) Print current command.
   prompt    (\R) Change your mysql prompt.
   quit      (\q) Quit mysql.
   rehash    (\#) Rebuild completion hash.
   source    (\.) Execute an SQL script file. Takes a filename as an argument.
   status    (\s) Get status information from the server.
   system    (\!) Execute a system shell command.
   tee       (\T) Set outfile [to_outfile]. Append everything into given outfile.
   use       (\u) Use another database. Takes database name as argument.
   charset   (\C) Switch to another charset. Might be needed for processing binlog with multi-byte charsets.
   warnings  (\W) Show warnings after every statement.
   nowarning (\w) Don't show warnings after every statement.
   
   For server side help, type 'help contents'
   
   MariaDB [(none)]>

4. Grant access to the database you created when launching the Quick Deploy App for the MySQL user.

   In this example, the database is called webdata, the user webuser, and the password for the user is p@ssw0rd. Your password needs to be different from the root password for MySQL.

   Bash

   GRANT ALL ON webdata.* TO 'webuser' IDENTIFIED BY 'p@ssw0rd';

5. Enter the exit command to leave MySQL/MariaDB.

Create a sample table

1. Log back in as the MySQL user by running the sudo mysql -u webuser -p command. In this example, the MySQL user is webuser.

2. Create a sample table called customers.

   Bash

   use webdata;
   create table customers (customer_id INT NOT NULL AUTO_INCREMENT PRIMARY KEY, first_name TEXT, last_name TEXT);

   This creates a table with:

   • A customer ID field of type INT for an integer (auto-incremented for new records, used as the primary key).
   • Two fields for storing the customer’s name. In this example, webdata is the database that you created when launching the Quick Deploy App.

3. View the contents of the table you created.

   CommandOutput

   describe customers;

   +-------------+---------+------+-----+---------+----------------+
   | Field       | Type    | Null | Key | Default | Extra          |
   +-------------+---------+------+-----+---------+----------------+
   | customer_id | int(11) | NO   | PRI | NULL    | auto_increment |
   | first_name  | text    | YES  |     | NULL    |                |
   | last_name   | text    | YES  |     | NULL    |                |
   +-------------+---------+------+-----+---------+----------------+

4. Enter the exit command to leave MySQL/MariaDB.

Additional resources

For more information about the installed packages, see their official documentation.

• MySQL Reference Manual
• PHP MySQL Manual
• MySQLdb User’s Guide

For more information about MySQL/MariaDB, see our official documentation.

• MariaDB Clusters with Galera