I assume you have read Setting up MySQL Router before reading this.
About different mode options :
[routing:read_only] :
If you connect a client to read-only routing service i.e. port 7001 , router will redirect the first connection to the first available server in the list, i.e. 13002. If you connect another client to the same bind_port, router will redirect the connection to the next available server in the list, i.e. 13003. another client request to same bind port will be redirected to next available server in the list , i.e 13004 and then router goes back to 13002.
So, when "mode = read-only" , client connection requests will be served in round-robin fashion. If next available server in the configured list in not available (may be its not running or its down), then following available server will be considered to serve the client requests.
[routing:read_write] :
If you connect a client to read-write routing service i.e. port 7002 , router will always redirect the connection to the first available server in the list, i.e. 13005. If you connect another client to the same bind_port, router will again redirect the connection to first available server in the list, i.e. 13005.
So, when "mode = read-write" , always first available server will be returned to the client. If the first available server in the configured list is not available (may be its not running or its down), then next available server in the list will be considered to serve the client requests.
About bind_address and bind_port :
Bind address is an optional parameter ,if you don't set it 127.0.0.1 will be assumed. bind_port is a mandatory config parameter, not specifying this will throw an error during the router start. Also a single bind_port can be used for multiple bind_address values.
For Example :
bind_address = localhost
bind_port = 7002
Default and logger sections are optional which deals with router log file paths,plugin (.so)paths and log levels.
Fabric cache section : It takes address where the state store is running and the user for connecting to the fabric setup. When the router is started it prompts for the corresponding password.
So we start our First example with the config file used in Setting up MySQL Router sample-router.ini
[logger]
level = INFO
[routing:read_only]
bind_address = localhost
bind_port = 7001
destinations = localhost:13002,localhost:13003,localhost:13004
mode = read-only
[routing:read_write]
bind_address = localhost
bind_port = 7002
destinations = localhost:13005,localhost:13006
mode = read-write
About different mode options :
[routing:read_only] :
If you connect a client to read-only routing service i.e. port 7001 , router will redirect the first connection to the first available server in the list, i.e. 13002. If you connect another client to the same bind_port, router will redirect the connection to the next available server in the list, i.e. 13003. another client request to same bind port will be redirected to next available server in the list , i.e 13004 and then router goes back to 13002.
So, when "mode = read-only" , client connection requests will be served in round-robin fashion. If next available server in the configured list in not available (may be its not running or its down), then following available server will be considered to serve the client requests.
[routing:read_write] :
If you connect a client to read-write routing service i.e. port 7002 , router will always redirect the connection to the first available server in the list, i.e. 13005. If you connect another client to the same bind_port, router will again redirect the connection to first available server in the list, i.e. 13005.
So, when "mode = read-write" , always first available server will be returned to the client. If the first available server in the configured list is not available (may be its not running or its down), then next available server in the list will be considered to serve the client requests.
About bind_address and bind_port :
Bind address is an optional parameter ,if you don't set it 127.0.0.1 will be assumed. bind_port is a mandatory config parameter, not specifying this will throw an error during the router start. Also a single bind_port can be used for multiple bind_address values.
For Example :
bind_address = localhost
bind_port = 7002
Now we start our Second Example with the <tar-package>/share/doc/mysqlrouter/sample_mysqlrouter.ini file which is part of the downloaded package :
[DEFAULT]
logging_folder =
plugin_folder = /usr/local/lib/mysqlrouter
config_folder = /etc/mysql
runtime_folder = /var/run
[logger]
level = INFO
[fabric_cache]
address = your_fabric_node.example.com:32275
user =
[routing:basic_failover]
bind_port = 7001
mode = read-write
destinations = mysql-server1:3306,mysql-server2
[routing:homepage_reads_fabric]
bind_port = 7002
destinations = fabric+cache:///group/homepage_group?allow_primary_reads=yes
mode = read-only
Default and logger sections are optional which deals with router log file paths,plugin (.so)paths and log levels.
Fabric cache section : It takes address where the state store is running and the user for connecting to the fabric setup. When the router is started it prompts for the corresponding password.
Fabric routing section : In this, a fabric
group is configured as destination. So based on one of the 2 possible
modes "read-only" or "read-write" , it will
redirect the connections to primary(read-write) or
secondaries(read-only) respectively.
If "allow_primary_reads=yes” is appended to
the destinations uri with read only mode, then primary also will be
considered in the list of servers available to router for processing
client requests. "allow_primary_reads" option does not make
any sense if the configured mode is read-write.
So in the above example configurations, connecting a
client to bind port 7002 , will return a connection to the server
available in the group named "homepage_group". In our
example allow_primary_reads=yes, so it can return any server from the
secondaries or primary. If only one slave is present in the group and
"allow_primary_reads=no", then the same server will be
handling the client requests. Connecting a client to the port 7001
will always return the first server available in the destinations
list. i.e. mysql-server1:3306. If this first server is not available
then it will return mysql_server2.
To learn more about integrating router with fabric High availability using Router
To learn more about integrating router with fabric High availability using Router
