Server Picker

SQreamDB’s load balancer is called server_picker.

Command Line Arguments

Parameters

Argument

Default

Description

--metadata_server_port

3105

The metadata server listening port

--metadata_server_ip

127.0.0.1

The metadata server IP

--port

3108

The server picker port

--ssl_port

3109

The server picker ssl port

--log4_config

/home/sqream/sqream3/etc/server_picker_log_properties

The server picker log4 configuration file to use

--refresh_interval

15

Refresh interval time to check available nodes

--services

None

Lists services separated by comma

--help

None

Used to display a help message or documentation for a particular program or command

Example

server_picker --metadata_ip=127.0.0.1 --metadata_server_port=3105 --port=3118 --ssl_port=3119 --services=sqream23,sqream0 --log4_config=/home/sqream/metadata_log_properties --refresh_interval=10

Starting server picker

Starting temporarily

In general, you should not need to run server_picker manually, but it is sometimes useful for testing.

Assuming we have a metadata server listening on the localhost, on port 3105:

nohup server_picker --metadata_server_ip=127.0.0.1 metadata_server_port=3105 &
SP_PID=$!

Using nohup and & sends server picker to run in the background.

Starting temporarily with non-default port

Tell server picker to listen on port 2255 for unsecured connections, and port 2266 for SSL connections.

nohup server_picker --metadata_server_ip=127.0.0.1 --metadata_server_port=3105 --port=2255 --ssl_port=2266 &
SP_PID=$!

Using nohup and & sends server picker to run in the background.

Stopping server picker

kill -9 $SP_PID

Tip

It is safe to stop any SQream DB component at any time using kill. No partial data or data corruption should occur when using this method to stop the process.