Wednesday, November 16, 2022

Secured MySQL InnoDB Cluster with Certificate creation using OpenSSL

This is a demo tutorial to show how we can create InnoDB Cluster with newly installed Certificate and having X509 certificate verification via MySQL Router connection.   

Recorded Video

The full process is recorded on Youtube - showing creating InnoDB Cluster with newly installed CA, Server Certificates.  The Router creation is configured with SSL Server certificate from the same CA certificate across Server nodes.   The creation of User (create user my509user identified by '....' require X509) using X509 certificate PASSTHROUGH verification via Router connection.


The following environment was tested 

Oracle Linux Server release 8.6

MySQL Server 8.0.31

MySQL Shell 8.0.31

MySQL Router 8.0.31

Github Script

The github script provides the steps to guide thru Installation of 3 nodes

To configure the node1/node2/node3 hostname under ./   (Change the hostname based on your environment)


export HOST1=workshop20

export HOST2=workshop22

export HOST3=workshop23



The creation of InnoDB Cluster creates Internal User (mysql_innodb_cluster_<server_id>@'%') 

Here is an example :

mysql> select user,host from mysql.user;


| user                     | host        |


| gradmin                  | %           |

| mysql_innodb_cluster_101 | %           |

| mysql_innodb_cluster_201 | %           |

| mysql_innodb_cluster_301 | %           |

| mysql.infoschema         | localhost   |

| mysql.session            | localhost   |

| mysql.sys                | localhost   |

| root                     | localhost   |


8 rows in set (0.00 sec)

Note : the RENAME USER does not work.

 (e.g.  mysql > rename user mysql_innodb_cluster_101@'%' to mysql_innodb_cluster_101@'10.0.%' )  

"%" as host may can be restricted to specific IP subnet via replicationAllowedHost option with MySQL Shell Admin API.   

As an example to restrict user creation with Host from subnet

mysql-js> dba.createCluster('testCluster', {replicationAllowedHost:''})

Group Replication with communication stack "MYSQL" goes through the standard MySQL port (for example 3306.  The encrypted communication / recovery channel is established with SSL certificate.    

group_replication_ssl_mode  is configured as REQUIRED to ensure secured SSL between nodes.


Establish a secure connection if the server supports secure connections.

group_replication_ssl_mode can also be configured as VERIFY_CA to ensure certificate being used and verified.

Like REQUIRED, but additionally verify the server TLS certificate against the configured Certificate Authority (CA) certificates.

The following sections describe the steps to setup the VERIFY_CA option and creation of certificates using OpenSSL command.

1. On each node to initialize MySQL Data Directory [ Script

2. Create CA certificate on Node1 and using the same CA certificate to create server-cert.pem for each server 
Refer to CA creation [ Script ]
Refer to Server certificate creation [ Script

3. Startup the server with unique $SERVER_ID on each HOST [ Script

4.On each host, configure Group Replication Admin User [ Script

5. Create 3 nodes Innodb Cluster with MySQL Shell with specific options to secure the SSL connection

6. Bootstrap MySQL Router [ Script ]

7. Create Router Certificate with same CA certificate and Configure the mysqlrouter.conf  

8. Start Router [ Script

9 Finally, creating a user with X509 and Login via MySQL Router
    Login to Primary Server with 'root'
mysql > create user my509user@'%' identified by 'my509pass' REQUIRE X509;

     Alternatively, user creation can follow more constraint with 



    For example (Check with the client certificate for the ISSUER or SUBJECT content  [ openssl x509 -text -in <certificate file> ] )

    example 1 : mysql > create user my509user@'%' identified by 'my509pass' REQUIRE ISSUER "/O=MySQL/CN=MySQL" ;

    example 2 : mysql > create user my509user@'%' identified by 'my509pass' REQUIRE SUBJECT "/CN=hostname";

    example 3 : mysql > create user my509user@'%' identified by 'my509pass' REQUIRE SUBJECT "/CN=hostname" AND ISSUER "/O=MySQL/CN=MySQL;


    Login using certificate via the Router  For example : (Given that the 'client-key.pem' 'client-cert.pem' is created on each host)
mysql -umy509user -pmy509pass -h127.0.0.1 -P6446 --ssl-mode=VERIFY_CA --ssl-ca=~/data/3310/ca.pem --ssl-cert=~/data/3310/client-cert.pem --ssl-key=~/data/3310/client-key.pem 



  1. REQUIRE X509 is not really user authentication, but just CA validation of the client cert.

    I'd argue you'd need REQUIRE SUBJECT in your user grant authenticate a precise certificate is coming from the client. Router does not seem to play well with this concept:

    1. Thanks for this great comment. The article has just been modified to include your valuable info.