The transaction safety was checked even if master GTID registration was
disabled. This always caused a failure when the router was started without
the transaction safety parameter.
As transaction safety is required by the GTID registration, it is not very
helpful to refuse to start if an invalid set of options is detected. To
make usage of the master GTID registration easier, the transaction safety
is also automatically enabled.
From the documentation:
* `never`: When there is an active transaction, no data will be returned
from the cache, but all requests will always be sent to the backend.
The cache will be populated inside _explicitly_ read-only transactions.
Inside transactions that are not explicitly read-only, the cache will
be populated _until_ the first non-SELECT statement.
* `read_only_transactions`: The cache will be used and populated inside
_explicitly_ read-only transactions. Inside transactions that are not
explicitly read-only, the cache will be populated, but not used
_until_ the first non-SELECT statement.
* `all_transactions`: The cache will be used and populated inside
_explicitly_ read-only transactions. Inside transactions that are not
explicitly read-only, the cache will be used and populated _until_ the
first non-SELECT statement.
With this variables set to true, if $VAR is used as a value in the
configuration file, then `$VAR` will be replaced with the value of
the environment variable VAR.
The total timeout for the retrying of interrupted queries can now be
configured with the `query_retry_timeout` parameter. It controls the total
timeout in seconds that the query can take.
The actual connection, read and write timeouts of the connector aren't a
good configuration value to use for abstracted queries as the time that it
takes to execute a query can be composed of both connections, reads and
writes. This is caused by the usage of MYSQL_OPT_RECONNECT that hides the
fact that the connector reconnects to the server when a query is
attempted.
The new `query_retries` parameter controls how many times an interrupted
query is retried. This retrying of interrupted queries will reduce the
rate of false positives that MaxScale monitors detect.
When the database firewall filter is used in white-list mode,
'USE <db>' should be allowed. When connecting, it is always
possible to specify the database anyway so restricting
'USE <db>' serves no purpose.
The avrorouter now uses the parameters from the source service. This
removes the need for redundant parameter definition in the avrorouter
service when they are defined in the binlogrouter service as parameters.
Added some missing configuration sanity checks and updated the tutorial to
reflect the new configuration method introduced in 2.1.
The documentation stated that the binlogrouter would use the cache
directory to store the binary log files. In reality, there was no default
value and the service would fail to start without a binlogdir parameter.
The router now uses the data directory (/var/lib/maxscale/) to store the
binary logs.
Set the default value of mariadb10-compatibility to true. This is in line
with the fact that most installations should use the router with a MariaDB
10.0 server or newer.