The recommended deployment of MySQL Router is on the same host as the application. When using a sandbox deployment, everything is running on a single host, therefore you deploy MySQL Router to the same host. When using a production deployment, we recommend deploying one MySQL Router instance to each machine used to host one of your client applications. It is also possible to deploy MySQL Router to a common machine through which your application instances connect. For more information, see Installing MySQL Router.
To bootstrap MySQL Router based on an InnoDB Cluster or
InnoDB ReplicaSet, you need the URI-like connection string to
an online instance. Run the mysqlrouter
command and provide the
instance is the
URI-like connection string to an online instance. MySQL Router
connects to the instance and uses the included metadata cache
plugin to retrieve the metadata, consisting of a list of server
instance addresses and their role. For example:
$> mysqlrouter --bootstrap icadmin@ic-1:3306 --account=mysqlrouter
You are prompted for the instance password and encryption key for MySQL Router to use. This encryption key is used to encrypt the instance password used by MySQL Router to connect to the cluster. The ports you can use for client connections are also displayed. For additional bootstrap related options, see Bootstrapping Options.
At this point MySQL Router has not been started so that it would route connections. Bootstrapping is a separate process.
The MySQL Router bootstrap process creates a
mysqlrouter.conf file, with the settings
based on the metadata retrieved from the address passed to the
option, in the above example
icadmin@ic-1:3306. Based on the metadata
retrieved, MySQL Router automatically configures the
mysqlrouter.conf file, including a
metadata_cache section. If you are using
MySQL Router 8.0.14 and later, the
automatically configures MySQL Router to track and store active
MySQL metadata server addresses at the path configured by
This ensures that when MySQL Router is restarted it knows which
MySQL metadata server addresses are current. For more
information, see the
In earlier MySQL Router versions, metadata server information was
defined during MySQL Router's initial bootstrap operation and stored
in the configuration file, which contained the addresses for all
server instances in the cluster. For example:
[metadata_cache:prodCluster] router_id=1 bootstrap_server_addresses=mysql://icadmin@ic-1:3306,mysql://icadmin@ic-2:3306,mysql://icadmin@ic-3:3306 user=mysql_router1_jy95yozko3k2 metadata_cluster=prodCluster ttl=300
If using MySQL Router 8.0.13 or earlier, when you change the
topology of a cluster by adding another server instance after
you have bootstrapped MySQL Router, you need to update
based on the updated metadata. Either restart MySQL Router using
--bootstrap option, or
manually edit the
section of the
mysqlrouter.conf file and
restart MySQL Router.
The generated MySQL Router configuration creates TCP ports which you use to connect to the cluster. By default, ports for communicating with the cluster using both classic MySQL protocol and X Protocol are created. To use X Protocol the server instances must have X Plugin installed and configured, which is the default for MySQL 8.0 and later. The default available TCP ports are:
6446- for classic MySQL protocol read-write sessions, which MySQL Router redirects incoming connections to primary server instances.
6447- for classic MySQL protocol read-only sessions, which MySQL Router redirects incoming connections to one of the secondary server instances.
64460- for X Protocol read-write sessions, which MySQL Router redirects incoming connections to primary server instances.
64470- for X Protocol read-only sessions, which MySQL Router redirects incoming connections to one of the secondary server instances.
Depending on your MySQL Router configuration the port numbers might
be different to the above. For example if you use the
--conf-base-port option, or
variable. The exact ports are listed when you start MySQL Router.
The way incoming connections are redirected depends on the
underlying topology being used. For example, when using a
single-primary cluster, by default MySQL Router publishes a
X Protocol and a classic MySQL protocol port, which clients connect
to for read-write sessions and which are redirected to the
cluster's single primary. With a multi-primary cluster
read-write sessions are redirected to one of the primary
instances in a round-robin fashion. For example, this means that
the first connection to port 6446 would be redirected to the
ic-1 instance, the second connection to port 6446 would be
redirected to the ic-2 instance, and so on. For incoming
read-only connections MySQL Router redirects connections to one of
the secondary instances, also in a round-robin fashion. To
modify this behavior see the
Once bootstrapped and configured, start MySQL Router. If you used a
system wide install with the
--bootstrap option then
$> mysqlrouter &
If you installed MySQL Router to a directory using the
--directory option, use the
start.sh script found in the directory you
installed to. Alternatively set up a service to start MySQL Router
automatically when the system boots, see
Starting MySQL Router. You can
now connect a MySQL client, such as MySQL Shell to one of the
incoming MySQL Router ports as described above and see how the
client gets transparently connected to one of the server
$> mysqlsh --uri root@localhost:6442
To verify which instance you are actually connected to, simply
issue an SQL query against the
port status variable.
mysql-js> \sql Switching to SQL mode... Commands end with ; mysql-sql> select @@port; +--------+ | @@port | +--------+ | 3310 | +--------+