Changes in MySQL Router 8.0.27 (2021-10-19, General Availability)

• Functionality Added or Changed

• Bugs Fixed

Functionality Added or Changed

• Added a new max_total_connections option that defines the maximum number of connections allowed by all Router destinations combined.

  The existing max_connections option still functions and allows setting the maximum number of connections per specific routing destination. (WL #14319)

• Added support for InnoDB ClusterSet topology and failover. This adds two new bootstrap command line configuration options that define the target_cluster metadata option at bootstrap: --conf-target-cluster (configure by cluster type) and --conf-target-cluster-by-name (configure using a static cluster name).

  The following ClusterSet values are added to Router's state file:

  • clusterset-id: ID of the ClusterSet Router was bootstrapped against.

  • metadata-servers: Set of all known ClusterSet metadata servers. Typically all nodes of all clusters in the ClusterSet.

  • view-id: ID of the last known view of the metadata.

  InnoDB ClusterSet support requires the cluster_type option set to gr. (WL #12797)

Bugs Fixed

• Now accept Client::Greeting messages that announce PLUGIN_AUTH but don't send a plugin name; this to be more flexible with the spec, like MySQL Server is. (Bug #33357723)

• Bootstrapping on systems with the older metadata version 1.0 now sets backend=file as metadata 1.0 does not support http_auth_backend. (Bug #33308536)

• Support for the following compilers was removed: Sun Studio, C++11, and C++14. (Bug #33307865, Bug #33306219, Bug #33302907)

• Receiving an empty xproto packet would cause Router to unexpectedly halt. (Bug #33240637)

• Updated error logs:

  Max total active connections errors now reference the associated max_total_connections parameter name.

  A failed connection reported "generic:1, operation not permitted." instead of "connection refused". (Bug #33051998, Bug #33059504)

• The Linux epoll IO service dropped events when multiple events fired at the same time. (Bug #32998738)

• Improved HTTP authentication efficiency by caching credentials per connection. (Bug #32981242)

• Defining a Router configuration option using an unsupported value would emit the associated error three times instead of once. (Bug #32949289)

• On Windows, the server_ssl_capath or server_ssl_crlpath Router configuration options did not function, and defining them caused Router to not start. (Bug #32859961)

• Router would repeat error or warning messages every TTL when failing to refresh the metadata thus filling up the logs. Now the log level is lowered (usually to level debug) if a given event had already been reported. (Bug #32423845)