The Ultimate Guide to High Availability with MariaDB
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maxscale can not make queries forward to slave

This is a config file for maxscale blow:

[maxscale]
threads=8

[server1]
type=server
address=192.168.8.61
port=3306
protocol=MySQLBackend

[server2]
type=server
address=192.168.8.74
port=3306
protocol=MySQLBackend

[MySQL Monitor]
type=monitor
module=mysqlmon
servers=server1,server2
user=test
passwd=test
monitor_interval=10000

[Read-Write Service]
type=service
router=readwritesplit
servers=server1,server2
user=test
passwd=test
max_slave_connections=100%
max_slave_replication_lag=30

[MaxAdmin Service]
type=service
router=cli

[Read-Write Listener]
type=listener
service=Read-Write Service
protocol=MySQLClient
port=4006



[MaxAdmin Listener]
type=listener
service=MaxAdmin Service
protocol=maxscaled
port=6603

There is the result that I execute "select * from test" 30 times via a mysql client and execute command "maxadmin -pmariadb show services"

Service:                             Read-Write Service
	Router:                              readwritesplit (0x7fd9ab9e02c0)
	State:                                       Started
	Number of router sessions:           	30
	Current no. of router sessions:      	0
	Number of queries forwarded:          	30
	Number of queries forwarded to master:	30
	Number of queries forwarded to slave: 	0
	Number of queries forwarded to all:   	30
	Master/Slave percentage:		100.00%
	Started:                             Thu Aug  4 11:27:30 2016
	Root user access:                    Disabled
	Backend databases
		192.168.8.74:3306  Protocol: MySQLBackend
		192.168.8.61:3306  Protocol: MySQLBackend
	Users data:                          0x1b28a40
	Total connections:                   31
	Currently connected:                 1

As we can see above, no query forward to slave server. how to resolve? please

Answer Answered by Markus Mäkelä in this comment.

Were the selects done inside a transaction or through a prepared statement? Was autocommit off?

You can also enable the info log level by adding log_info=1 under the [maxscale] section. This will tell you what routing decisions the readwritsplit is making.

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