MySQL Router 8.0.16: What’s new

MySQL Router 8.0.16

Key features

• log-rotation via SIGHUP
• HTTP server plugin
• flexible support for single/multi-PRIMARY Group Replication

Logrotation via SIGHUP

Sending a SIGHUP signal to the router process will now close and reopen the logfile.

It allows the integration with the logrotate to rotate and compress the Router’s logfiles.

HTTP server plugin

Support for running a HTTP server inside the mysqlrouter has been added

Motivation

The HTTP server plugin builds the foundation for features like:

• Monitoring
• Management

which will appear in the upcoming releases of MySQL Router.

In 8.0.16 it already supports:

• encrypted connections via TLS (up to 1.3 if linked against openssl 1.1.1)
• Authentication
• sending static-files

Configuration

The plugin is disabled by default and can be enabled by:

[http_server]
port=8080

To enable HTTPS a certificate has to be provided:

[http_server]
port=8443
ssl=1
ssl_cert=server-cert.pem
ssl_key=server-key.pem

To serve static files the http_server plugin needs the know the base-directory:

[http_server]
port=8443
ssl=1
ssl_cert=server-cert.pem
ssl_key=server-key.pem
static_folder=/var/www/example.com/wwwroot/

To enforce authentication a hashed password storage is needed that can be greated by the new mysqlrouter_passwd utility:

$ mysqlrouter_passwd set /tmp/router.htpasswd example_user

The file contains salted hashed passwords which can be used as authentication backend:

[http_auth_backend:example_backend]
backend=file
filename=/tmp/router.htpasswd

Currently passwd file supports the salted functions:

• sha256-crypt (default)
• sha512-crypt
• pbkdf2-sha256
• pbkdf2-sha512

As last setup the router’s configuration has to connect the password storage with the http-server via a auth realm:

[http_auth_realm:secure_realm]
backend=example_backend
method=basic
name=secret area
 
[http_server]
# ...
require_realm=secure_realm

Single/Multi-PRIMARY

MySQL Router’s bootstrap command generates the configuration for the MySQL Router in MySQL InnoDB cluster setups.

It sets up two ports:

• one for read-write connections
• one for read-only connections

Before 8.0.16, when MySQL Router detected a multi-PRIMARY Group Replication setup at bootstrap it generated only the “read-write” port which meant that if one of the PRIMARYs becomes a SECONDARY there would be no way to connect to it through the router.

In 8.0.16 the bootstrap has been changed to always generate a “read-only” port and route connections that come in via the read-only port to one of the PRIMARYs in case no SECONDARY exists currently (see routing-strategy=round-robin-with-fallback )

empty state.json fixed

MySQL 8.0.15 started to write the last known address of the metadata-servers into the state.json file.

In case there was a failure to reach the metadata-server’s an empty server-list was written to the state.json which meant a Router wouldn’t be able to restart anymore. This has been fixed in 8.0.16 (see Bug #94057 )