无法在Ubuntu上启动mariadb MaxScale服务

Question

I'm running Ubuntu 16.04 with mariadb,

And I've downloaded maxscale on the official website, installed,

https://downloads.mariadb.com/MaxScale/2.0.4/ubuntu/dists/xenial/main/binary-amd64/maxscale-2.0.4-1.ubuntu.xenial.x86_64.deb

And now I can't start the service, not so helpful

2017-02-28 11:41:11   notice : Working directory: /var/log/maxscale
2017-02-28 11:41:11   notice : MariaDB MaxScale 2.0.4 started
2017-02-28 11:41:11   notice : MaxScale is running in process 21493
2017-02-28 11:41:11   notice : Configuration file: /etc/maxscale.cnf
2017-02-28 11:41:11   notice : Log directory: /var/log/maxscale
2017-02-28 11:41:11   notice : Data directory: /var/lib/maxscale
2017-02-28 11:41:11   notice : Module directory: /usr/lib/x86_64-linux-gnu/maxscale
2017-02-28 11:41:11   notice : Service cache: /var/cache/maxscale
2017-02-28 11:41:11   notice : No query classifier specified, using default 'qc_sqlite'.
2017-02-28 11:41:11   notice : Loaded module qc_sqlite: V1.0.0 from /usr/lib/x86_64-linux-gnu/maxscale/libqc_sqlite.so
2017-02-28 11:41:11   error  : Failed to start all MaxScale services. Exiting.
2017-02-28 11:41:11   MaxScale is shut down.

/etc/maxscale.cnf

[maxscale]
threads=1

[server1]
type=server
address=127.0.0.1
port=3306
protocol=MySQLBackend

Any ideas?

Answer 1

The reason why it fails to start is because you didn't define a service. Although this is explained in the error message, it's not quite easy to interpret: 2017-02-28 11:41:11 error : Failed to start all MaxScale services. Exiting. 2017-02-28 11:41:11 error : Failed to start all MaxScale services. Exiting.

Try adding the following three objects into your configuration:

[Read-Connection-Router]
type=service
router=readconnroute
servers=server1
user=maxuser
passwd=maxpwd

[Read-Connection-Listener]
type=listener
service=Read-Connection-Router
protocol=MySQLClient
port=4008

[MySQL-Monitor]
type=monitor
module=mysqlmon
servers=server1
user=maxuser
passwd=maxpwd
monitor_interval=1000

The Read-Connection-Router is the service that MaxScale provides. The Read-Connection-Listener is the network port where clients can connect and it links to the previously defined service. The last object, MySQL-Monitor , is the database monitor which actively monitors the state of the database servers.

The mysqlmon module defined in the configuration is for the standard Master-Slave replication clusters. If you're using Galera clusters, you'd want to use the galeramon module.