Administering the Command Center Web Server

The gpccws web server binary and web application files are installed in the bin directory of your Greenplum Command Center installation.

Starting and Stopping the Web Server

Starting the Command Center Web Server runs the gpccws web server, starts the metrics collection agents on the segment servers, and starts a listener on the Command Center rpc port.

You can run the gpcc command as the gpadmin user on the standby master host (recommended) or on the master host.

To ensure the gpcc command is on your path, source the file in the Command Center installation directory or add it to the startup script for your command shell. See Setting the Greenplum Command Center Environment for instructions.

The gpcc command uses the gpmon role to connect to Greenplum Database. It looks for the gpmon password in the PGPASSWORD environment variable or in the .pgpass file in the gpadmin user’s home directory. You can instead append the -W flag to the gpcc commands below to have gpcc prompt you to enter the password.

To start Greenplum Command Center

Log on to the standby master host or the master host.

To log on to the standby from the master host:

$ ssh <standby-host>

Source the Command Center environment variables.

$ source /usr/local/greenplum-cc-<version>/gpcc_path.

Start the Command Center web server and the metrics collection agents.

$ gpcc start
Starting the gpcc agents and webserver…
2018/03/22 17:35:06 Agent successfully started on 7/8 hosts
2018/03/22 17:35:06 View Greenplum Command Center at http://smdw:28080

To stop Greenplum Command Center

$ gpcc stop
2018/03/22 17:36:23 Gpcc webserver and metrics collection agents have been stopped. Use gpcc start to start them again

To check the Greenplum Command Center status

$ gpcc status
Starting the gpcc agents and webserver…
2018/03/22 17:36:55 Agent successfully started on 7/8 hosts
2018/03/22 17:36:55 View Greenplum Command Center at http://smdw:28080

See the gpcc reference page for full syntax for the gpcc command.

Configuring the Command Center Web Server

The web server configuration file is stored in $GPCC_HOME/conf/app.conf. The parameters in this configuration file are set when you install Greenplum Command Center. The installer copies the Command Center installation directory, including this configuration file, to every Greenplum Database host.

See the Web Server Parameters section of Configuration File Reference for a description of the parameters in this file.

You can see a summary of the current configuration using the gpcc --settings command.

$ gpcc --settings
Install path:   /usr/local
Display Name:   gpcc
GPCC port:      28080
Kerberos:       disabled
SSL:            disabled

If you modify the file on one host you should copy it to every other host. Be sure to restart the web server after you change the configuration. Rather than modifying the configuration directly, you can just stop Command Center and re-run the gpccinstall-<version> installation command. This ensures the configuration is consistent on all hosts.

You can use the gpcc krbenable command to add Kerberos authentication to the Command Center configuration. See Enabling Authentication with Kerberos for details about setting up Kerberos on the Command Center host. The gpcc krbenable command prompts for the Kerberos principal names and artifacts and updates the configuration.

The gpcc krbdisable command removes Kerberos parameters from the Command Center configuration.

Viewing and Maintaining Web Server Log Files

Web server access and error log messages are written to $GPCC_HOME/logs/gpccws.log.

If you experience errors viewing the Greenplum Command Center Console, refer to this file for more information.

To prevent the web server log from growing to excessive size, you can set up log file rotation using logrotate or cronolog.