By default, MySQL Router scans specific locations for its configuration files that depend on the platform and how MySQL Router was set up.

You can alter the default locations at compile time by using the -DROUTER_CONFIGDIR=<path> option. You could also edit cmake/settings.cmake to change the default locations before compiling MySQL Router, thus adding new locations or exceptions for specific platforms.

Execute mysqlrouter --help to see the default configuration file locations (and their availability) on your system. For example:

$> mysqlrouter --help

...

Start MySQL Router.

Configuration read from the following files in the given order (enclosed
in parentheses means not available for reading):
  (/usr/local/mysql-router/mysqlrouter.conf)
  /Users/philip/.mysqlrouter.conf
Plugins Path:
  /usr/local/lib/mysqlrouter
Default Log Directory:
  /usr/local/mysql-router
Default Persistent Data Directory:
  /usr/local/mysql-router/data
Default Runtime State Directory:
  /usr/local/mysql-router/run

Usage: mysqlrouter [-v|--version] [-h|--help]

...

On Linux, MySQL Router scans the following locations by default, although these locations are system dependent:

Two command line options help control these configuration file locations:

For example:

$> mysqlrouter --config /custom/path/to/router.conf --extra-config /another/config.conf

Multiple extra configuration options can be passed in and the files are loaded in the order they are entered, with --config options being loaded before the --extra-config options. For example:

$> mysqlrouter --extra-config a.conf --config b.conf --extra-config c.conf

In the above example, b.conf is loaded first, and then a.conf and c.conf, in that order. Also, the default configuration file, such as /etc/mysqlrouter/mysqlrouter.conf, is not loaded because --config was used.

Each loaded configuration file overrides configuration settings from the previously read configuration files.

The following lists default file location for the router to read configuration files on popular Linux platforms.

Default file locations that MySQL Router searches for configuration files on Windows.

As of MySQL Router 8.4, the full configuration of routers bootstrapped against a InnoDB Cluster is stored in the InnoDB Cluster Metadata Schema and can be read by the MySQL Shell operation, object.routerOptions, for Cluster, ClusterSet, and ReplicaSets.

The configuration is stored per router as JSON in the mysql_innodb_cluster_metadata.routers table with one row per router. Each router's row is updated by the router on startup or restart.

For example:

        mysql>  select JSON_PRETTY(attributes->>'$.Configuration') as Configuration from mysql_innodb_cluster_metadata.routers \G
        
        Configuration: {
"io": {
    "backend": "poll",
    "threads": 0
},
"common": {
    "name": "system",
    "user": "",
    "read_timeout": 30,
    "client_ssl_key": "/Users/areliga/dev/server/mysql-trunk/build/pt/data/router-key.pem",
    "client_ssl_cert": "/Users/areliga/dev/server/mysql-trunk/build/pt/data/router-cert.pem",
    "client_ssl_mode": "PREFERRED",
    "connect_timeout": 5,
    "server_ssl_mode": "PREFERRED",
    "server_ssl_verify": "DISABLED",
    "max_total_connections": 512,
    "unknown_config_option": "error",
    "router_require_enforce": true,
    "max_idle_server_connections": 64
},
"loggers": {
    "filelog": {
    "level": "info",
    "filename": "mysqlrouter.log",
    "destination": "",
    "timestamp_precision": "second"
    }
},
"endpoints": {
    "bootstrap_ro": {
    
    ......
    
    }
   }
    
      

See Viewing Router Configurations with MySQL Shell for more information.

For backward compatibility, MySQL Router continues to store some configuration parameters in the attributes JSON in mysql_innodb_cluster_metadata.routers.

For example:

select JSON_PRETTY(attributes) from mysql_innodb_cluster_metadata.routers;
| {
  "ROEndpoint": "6447",
  "RWEndpoint": "6446",
  "ROXEndpoint": "6449",
  "RWXEndpoint": "6448",
  "RWSplitEndpoint": "6450",
  "MetadataUser": "mysql_router1_plje99d",
  "Configuration": { /*...*/ },
  "bootstrapTargetType": "cluster"
} |