metadata_server

SQream DB’s cluster manager/coordinator is called metadata_server.

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

Command Line Arguments

Argument

Default

Description

--config

/home/omert/.sqream/metadata_server_config.json

The configuration file to use

--port

3105

The metadata server listening port

--log_path

./metadata_server_logs

The metadata_server log file output contains information about the activities and events related to the metadata server of a system.

--log4_config

None

Specifies the location of the configuration file for the Log4cxx logging library.

--num_deleters

1

Specifies the number of threads to use for the file reaper in a system or program.

--metadata_path

<...sqreamd/leveldb>

Specifies the path to the directory where metadata files are stored for a system or program.

--help

None

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

Starting metadata server

Starting temporarily

nohup metadata_server -config ~/.sqream/metadata_server_config.json &
MS_PID=$!

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

Note

  • Logs are saved to the current directory, under metadata_server_logs.

  • The default listening port is 3105

Starting temporarily with non-default port

To use a non-default port, specify the logging path as well.

nohup metadata_server --log_path=/home/rhendricks/metadata_logs --port=9241 &
MS_PID=$!

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

Note

  • Logs are saved to the /home/rhendricks/metadata_logs directory.

  • The listening port is 9241

Stopping metadata server

To stop metadata server:

kill -9 $MS_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.