Installing and Upgrading VMware Greenplum Command Center

The VMware Greenplum Command Center installation utility installs the Command Center files on all hosts in the VMware Greenplum cluster.

Note: Run the Greenplum Command Center installer on the VMware Greenplum coordinator host. The installer installs the Command Center software on every host in your VMware Greenplum cluster. It retrieves the list of hosts in your VMware Greenplum cluster from the gp_segment_configuration system table.

After you have run the installer you can start Greenplum Command Center on the coordinator host (recommended) or on the standby coordinator host.

Prerequisites

Before installing or upgrading Greenplum Command Center, ensure the following requirements are met:

VMware Greenplum must be installed and running. See the VMware Greenplum Command Center release notes for compatible VMware Greenplum versions.
After installing a VMware Greenplum distribution, the shared_preload_libraries configuration parameter contains the metrics collector shared library. Make sure this library is still present:
```
$ gpconfig -s shared_preload_libraries
Values on all segments are consistent
GUC          : shared_preload_libraries
Master  value: metrics_collector
Segment value: metrics_collector
```
Check that the shared library exists at $GPHOME/lib/postgresql/metrics_collector.so. If the library does not exist, make sure you have installed the VMware Greenplum distribution. This extension is not available in the VMware Greenplum Open Source version.

If the shared library file exists in the $GPHOME/lib/postgresql directory, but not in the shared_preload_libraries parameter, add it with the gpconfig command:
```
$ gpconfig -c shared_preload_libraries -v 'metrics_collector'
```
Note that adding metrics_collector to the shared_preload_libraries parameter does not enable the metrics_collector or gp_wlm extensions, but is a prerequisite for enabling them.
The VMware Greenplum gp_enable_query_metrics configuration parameter must be set to on to enable query metrics collection (it is off by default). You must restart VMware Greenplum for changes to this parameter to take effect.
The VMware Greenplum COORDINATOR_DATA_DIRECTORY environment variable must be set.
The directory where Greenplum Command Center will be installed, /usr/local/ by default, must be writable by the gpadmin user on all VMware Greenplum hosts. See Selecting and Preparing an Installation Directory for Command Center.
Port 28080 (default) must be open to TCP connections from Web clients to the HTTP server on the coordinator and standby coordinator hosts. Greenplum Command Center web browser clients connect to this port to access the Command Center Console. Browser connections use HTTP/HTTPS and WebSocket (WS)/Secure WebSocket (WSS) protocols. A different port number can be specified when Command Center is installed. To access the Command Center web server through a proxy, the proxy must have WebSocket suport.
Port 8899 must be open on all hosts in the VMware Greenplum cluster for TCP connections. This is an RPC port, used by the metrics collection agents on the segment hosts to send metrics to the backend.
Command Center requires the Apache Portable Runtime Utility library. The library is no longer included in the VMware Greenplum lib directory, but it is installed as a dependency if you install the VMware Greenplum distribution with yum or apt. Run the command yum install apr-util or apt install libapr1 if you need to install the apr-util library.
If you choose to have Command Center server support SSL/TLS encryption for browser connections – the default behavior – you need a combined SSL certificate file containing the server certificate and private key. See SSL/TLS Encryption for more information.
Reserve the Command Center webserver port by setting the net.ipv4.ip_local_reserved_ports parameter in the /etc/sysctl.conf file to the Command Center’s web server port, which is 28080 by default.

Selecting and Preparing an Installation Directory for Command Center

The Command Center installation directory (default /usr/local) must exist and be writable by the gpadmin user on every host in the VMware Greenplum cluster. The Command Center installer creates a directory named greenplum-cc-<version> in this directory on every host. When Command Center installation is complete the greenplum-cc-<version> directory and all of its contents must be owned by the gpadmin user. If Command Center creates the greenplum-cc-<version> directory, it also creates a greenplum-cc symbolic link to it, providing the gpadmin user has permission to create the link. You can use the greenplum-cc link in your shell startup script to source the gpcc_path.sh file.

In a standard Linux system, the /usr/local directory is owned by root and is only writable by root. If you choose the default installation directory or another directory where gpadmin does not have write permission, the root user can create the Command Center directory and the symbolic link in the installation directory on each host and make gpadmin the owner. Then the gpadmin user can run the installer without error.

If the gpadmin user has sudo access, you can use the gpssh utility to create the directory and set the owner to gpadmin on all hosts with these commands:

$ source /usr/local/greenplum-db-<version>/greenplum_path.sh
$ gpssh -f <hostfile> 'sudo mkdir -p /usr/local/greenplum-cc-7.1.0; sudo chown -R gpadmin:gpadmin /usr/local/greenplum-cc-7.1.0'
$ gpssh -f <hostfile> 'sudo ln -s /usr/local/greenplum-cc-7.1.0 /usr/local/greenplum-cc'

The <hostfile> text file contains a list of all Greenplum host names, including the coordinator, standby coordinator, and segment hosts.

See the VMware Greenplum installation documentation for information about setting up passwordless SSH.

Install the Greenplum Command Center Software

Run the Greenplum Command Center installer on the VMware Greenplum coordinator host as the gpadmin user. The installer copies the software to all other hosts in the cluster.

Download the Greenplum Command Center distribution file for your VMware Greenplum version from Broadcom Support Portal and copy it to the gpadmin user’s home directory on the coordinator host.

Note
For more information about download prerequisites, troubleshooting, and instructions, see Download Broadcom products and software.
Extract the installer from the zip file.
```
$ unzip greenplum-cc-web-gp7-<version>-<platform>.zip
```
Extracting the installer creates a greenplum-web-<version> directory containing the gpccinstall-<version> installation utility.

There are four ways to run the Greenplum Command Center installer:

Interactive – the installer prompts you for the installation parameters.
Scripted – you run the installer with a configuration file containing installation parameters.
Upgrade – the installer uses the installation parameters from the current Command Center installation.
Auto – the installer uses default installation parameters.

Note: The Command Center installer uses HTTPS as the default protocol for the Command Center web server. If you choose HTTP instead, Command Center issues a warning message. The only exception is if you install with the -auto option, for which the default protocol is HTTP.

Interactive Installation

Source the greenplum_path.sh script in the VMware Greenplum installation directory to ensure the GPHOME environment variable is set.
```
$ source /usr/local/greenplum-db/greenplum_path.sh
```
Run the Greenplum Command Center installer.
```
$ cd greenplum-cc-<version>
$ ./gpccinstall-<version> 
```
You can add the following options to the gpccinstall command-line. - The -W option instructs the installer to prompt for the gpmon database user’s password. - If the gpmon user does not yet exist, the installer creates it using the password you enter at the prompt. The password is not saved anywhere, so be sure to remember the password you enter.
- If the gpmon user already exists, the installer uses the password you enter at the prompt for the gpmon user. It ignores any password set in the PGPASSWORD environment variable, or in the .pgpass file in the gpadmin user’s home directory (or in the file specified in the PGPASSFILE environment variable). - If the gpmon user already exists, but you do not specify the -W option, the installer uses the password set in the PGPASSWORD environment variable or in the .pgpass file. - If the gpmon user does not yet exist and you do not specify -W (or if you specify the -W option but enter no password at the prompt) the installer creates the gpmon user with a default password. See the .pgpass file to find the password. - The -ssh_path option allows you to specify the full path to a custom SSH program. If you do not supply this option, the installer uses the ssh command on the path. Example:
```
$ ./gpccinstall-<version> --ssh_path /usr/local/bin/ssh -W
```
- The -ipv6 option installs a version of Command Center with support for running on IPv6 networks. To enable IPv6, you must set the HTTPAddr configuration parameter in the $GPCC_HOME/conf/app.conf file to the IPv6 address of the host that runs Command Center.
- The -krbenable option includes prompts to configure Command Center Kerberos authentication. The Kerberos prompts are omitted from the installation dialog by default.
Where would you like to install Greenplum Command Center? (Default=/usr/local)

Press Enter to accept the default or enter the desired path. The directory must exist on all hosts in the VMware Greenplum cluster and must be writable by the gpadmin user. See Selecting and Preparing an Installation Directory for Command Center for more information.
What would you like to name this installation of Greenplum Command Center? (Default=gpcc)

Enter a name to display on Command Center web pages to identify this Greenplum Command Center installation.
What port would you like the gpcc webserver to use? (Default=28080)

The default Command Center listen port is 28080. Press Enter to accept the default or enter another port number.
(Optional). These prompts appear only if you specify -krbenable on the gpccinstall command line.

Enter webserver name for this instance: (Default=<gpcc-host>)

The Kerberos keytab file must contain a principal for the Command Center web server. The web server principal name has the the format HTTP/<gpcc-host>@<realm>, where <gpcc-host> is the host name clients use in URLs when connecting to the Command Center web server.

Enter the name of the Kerberos service: (Default=postgres)

The default Kerberos service name for VMware Greenplum is postgres.

Choose Kerberos mode (1.normal/2.strict/3.gpmon_only): (Default=1)

Greenplum Command Center supports three different Kerberos authentication schemes.

1 - normal mode (default) – The Command Center Kerberos keytab file contains the Command Center principal and may contain principals for Command Center users. If the principal in the client’s connection request is in the Command Center’s keytab file, Command Center uses the client’s principal for database connections. Otherwise, Command Center uses the gpmon user for database connections.
2 - strict mode – Command Center has a Kerberos keytab file containing the Command Center service principal and a principal for every Command Center user. If the principal in the client’s connection request is in the keytab file, the web server grants the client access and the web server connects to VMware Greenplum using the client’s principal name. If the principal is not in the keytab file, the connection request fails.
3 - gpmon_only mode – Command Center uses the gpmon database role for all VMware Greenplum connections. No client principals are needed in the Command Center’s keytab file.

Enter path to the keytab file

Enter the path to the keytab file containing the Kerberos principal for the Command Center web server and, optionally, Command Center user principals.

What is the URL of the Command Center web server?

The Kerberos keytab file must contain a principal for the Command Center web server. The principal name is in the format HTTP/<gpcc-host>@<realm>, where <gpcc-host> is the host name clients use in URLs when connecting to the Command Center web server.
Would you like to enable SSL?

Enter y if you want to enable SSL/TLS (HTTPS) encryption for client connections to the Command Center web server. The installation utility prompts for the location of the combined SSL certificate file.

Enter the full path of the certificate file, including file name

Enter the path to the combined SSL certificate file installed on the Command Center host. This file contains a certificate and a private key for the web server. The file must be readable by the gpadmin user. See SSL/TLS Encryption for information about creating this file and installing it on your server.
Choose a display language (Default=English)
1. English
2. Chinese
3. Korean
4. Russian
5. Japanese

Enter a number to choose a language for the Command Center user interface.

The installer saves a log of the installation session in the current directory in a file named gpccinstall.<timestamp>.log.

Update the Metrics Collector Extension

If you are installing Command Center into a VMware Greenplum version released before the Command Center version you are installing, the installer prompts you to update the metrics_collector extension. It writes a README file, update-extension.txt, in the new Command Center installation directory, which lists the steps to install the new extension.

To access new Command Center features you must do the following:

Remove the current metrics_collector extension.
Install the new extension.
Restart VMware Greenplum.

If a new VMware Greenplum metrics_collector extension is required, the installer displays the following message:

********************************************************************************
*                                                                              *
* INSTALLATION IS ALMOST COMPLETED                                             *
*                                                                              *
* The last step is to update the metrics_collector extension, which needs to   *
* restart the VMware Greenplum cluster. Please proceed to $GPCC_HOME and     *
* follow the instructions in this file:                                        *
*                                                                              *
*                            update-extension.txt                              *
*                                                                              *
* Some new features may not be available before the update is done.            *
*                                                                              *
* To use GPCC with the old metrics_collector extension, source gpcc_path.sh    *
* and run 'gpcc start'.                                                        *
*                                                                              *
********************************************************************************

If you are unable to restart VMware Greenplum at this time, you can source the gpcc_path.sh file in the newly installed Command Center directory and then restart Command Center. New Command Center features may not be available until you update the metrics collector extension and restart VMware Greenplum.

IMPORTANT: When updating VMware Greenplum to a newer version, DO NOT use gppkg migrate to migrate the previous metrics_collector. If you have to use gppkg migrate for some other packages, first run gppkg remove to remove metrics_collector from the old VMware Greenplum installation.

Follow these steps to upgrade the metrics_collector extension.

Source the gpcc_path.sh file in the new Command Center installation directory.
```
$ source <install-dir>/greenplum-cc/gpcc_path.sh
```
Change to the new Command Center home directory.
```
$ cd $GPCC_HOME
```

View and follow the instructions in the update-extension.txt file.

$ cat update-extension.txt

Please update metrics_collector extension with the following steps.
Skip if you just reinstalled GPCC without any changes to GPDB binary.
For more information please check the documentation.

######################################
#                                    #
#   I M P O R T A N T  N O T I C E   #
#                                    #
######################################

!!! GPDB RESTART is required. !!!

When upgrading GPDB to a newer version,
DO NOT use "gppkg --migrate" to migrate the previous metrics_collector.

If you have to use "gppkg --migrate" for some other packages,
first run "gppkg -r" to remove metrics_collector from the old GPDB installation.

Before you proceed with updating the metrics_collector extension,
be sure to back up these original files, in case you decide to roll back:

$GPHOME/lib/postgresql/metrics_collector.so
$GPHOME/share/postgresql/extension/metrics_collector*
$GPHOME/share/postgresql/extension/gp_wlm*

1. cd /usr/local/greenplum-cc-7.0.0/gppkg
2. Stop GPCC: gpcc stop
3. Drop extension: psql gpperfmon -c 'drop extension metrics_collector'
4. List the packages installed:
   After GPDB 7: gppkg query
   Before GPDB 7: gppkg -q --all
5. Remove the old version of the metrics_collector: 
   After GPDB 7: gppkg remove MetricsCollector"
   Before GPDB 7: gppkg -r MetricsCollector-"
6. Install the new version:
   After GPDB 7: gppkg install MetricsCollector-7.0.0_gp_7.0.0--.gppkg
   (NOTE: If "gppkg query" does not show any installed MetricsCollector packages, you may need to use 
   "gppkg instll -f" instead.)
   Before GPDB 7: gppkg -i MetricsCollector-7.0.0_gp_7.0.0--.gppkg
7. Restart GPDB
8. Restart GPCC: gpcc start

Note
When you install Vmware Greenplum Command Center 7 for the very first time, VMware Greenplum has a metrics collector extension that was not installed as a gppkg package, and gppkg query shows that no metrics collector extension exists. This leads to an error when you try to install the metrics collector package, similar to: Error: from ms7: IoError(file '/usr/local/greenplum-db-7.0.0/lib/postgresql/metrics_collector.so' exists in the filesystem. If you receive this error, install metrics collector using the gppkg --force option. For example: gppkg install --force ./MetricsCollector-7.0.0_gp_7.0.0-rocky8-x86_64.gppkg

Install With a Configuration File

You can provide a configuration file to the Greenplum Command Center installer to perform a non-interactive Command Center installation.

$ cd greenplum-cc-<version>
$ ./gpccinstall-<version> -c <config-file>

The following table contains the names of the parameters corresponding to the interactive installation prompts and their default values. Define parameters in a configuration file for any parameters that have no default value or to override default values.

Installer Prompt	Default	Parameter
Where would you like to install Greenplum Command Center?	/usr/local	path
What would you like to name this installation of Greenplum Command Center?	gpcc	display_name
What port would you like the gpcc webserver to use?	28080	web_port
Would you like to enable Kerberos?	false	enable_kerberos
Choose Kerberos mode (1.normal/2.strict/3.gpmon_only):	1	krb_mode
Please provide the path to the keytab file:		keytab
What is the name of the GPDB Kerberos service?	postgres	krb_service_name
What is the URL of the Command Center web server?	gpcc	webserver_url
Would you like to enable SSL?	true	enable_ssl
Please provide the file path for the SSL certificate:	/etc/ssl/certs/cert.pem	ssl_cert_file
Please choose a display language (1.English2.Chinese/3.Korean/4.Russian/5.Japanese)	1	language

If the enable_kerberos parameter is true, the keytab, webserver_url, krb_mode, and krb_service_name parameters must also be set.

If the enable_ssl parameter is true, the ssl_cert_file parameter is required.

The following installation configuration file example sets all parameters to their default values.

path = /usr/local
# Set the display_name param to the string to display in the GPCC UI.
# The default is "gpcc"
# display_name = gpcc

master_port = 5432
web_port = 28080
rpc_port = 8899
enable_ssl = false
# Uncomment and set the ssl_cert_file if you set enable_ssl to true.
# ssl_cert_file = /etc/certs/mycert
enable_kerberos = false
# Uncomment and set the following parameters if you set enable_kerberos to true.
# webserver_url = <webserver_service_url>
# krb_mode = 1
# keytab = <path_to_keytab>
# krb_service_name = postgres
# User interface language: 1=English, 2=Chinese, 3=Korean, 4=Russian, 5=Japanese
language = 1

Non-Interactive Installation with Defaults

The non-interative installation is useful when installing Command Center in a cloud environment.

Source the greenplum_path.sh script in the VMware Greenplum installation directory to ensure the GPHOME environment variable is set.
```
$ source /usr/local/greenplum-db/greenplum_path.sh
```
Run the Greenplum Command Center installer with the -auto option.
```
$ cd greenplum-cc-<version>
$ ./gpccinstall-<version> -auto
```

Note: When you run the installer with the -auto option, the Command Center installer uses HTTP as the default protocol for the Command Center web server. To override this, you must use the -c option to pass in a configuration file that has enable_ssl set to true and ssl_cert_file set to the cert file path.

Upgrade

Before you upgrade Command Center, you must have installed the new Command Center software. See Install the Greenplum Command Center Software.

Running gpccinstall with the -u option installs a Greenplum Command Center release using the configuration parameters from the current Command Center installation. You can install a new Command Center release, or reinstall the current release. This option is also useful after you have added new hosts to the VMware Greenplum cluster or replaced failed hosts.

The configuration parameters are read from the $GPCC_HOME/conf/app.conf file.

Source the greenplum_path.sh script in the VMware Greenplum installation directory to ensure the GPHOME environment variable is set.
```
$ source /usr/local/greenplum-db/greenplum_path.sh
```
Source the gpcc_path.sh script in the Greenplum Command Center installation directory.
```
$ source /usr/local/greenplum-cc-<version>/gpcc_path.sh
```
Run the Greenplum Command Center installer with the -u option.
```
$ cd greenplum-cc-<version>
$ ./gpccinstall-<version> -u
```

After the upgrade has completed, the Command Center installer may prompt you to update the VMware Greenplum metrics collector extension. See Update the Metrics Collector Extension for steps to complete this task.

Changed Location for the `gpmetrics` Directory Starting in Command Center 6.8

In Command Center 6.8, the gpmetrics directory default location changed to $HOME.

If you are upgrading from Command Center 6.7.x or earlier and a directory called gpmetrics does not already exist under $HOME, Command Center will migrate the gpcc.conf and gpcc-alert.yaml files from $COORDINATOR_DATA_DIRECTORY/gpmetrics directory to $HOME/gpmetrics.

If a directory called gpmetrics does already exist under $HOME, you must copy the gpcc.conf and gpcc-alert.yaml files over manually before starting Command Center 6.8.0 or later for the first time.

NOTE: To specify a default location different than $HOME for the gpmetrics directory, configure the gpmetrics_home parameter in the $GPCC_HOME/conf/app.conf file. For more information, see the Command Center Console Parameters topic.

Installing Multiple Command Center Instances

You can install a Command Center instance for each VMware Greenplum system installed on your cluster. This feature requires VMware Greenplum 6.8 or above.

Follow these steps when installing an additional Command Center instance.

Source the greenplum_path.sh file in the target VMware Greenplum system before you start the Command Center installer.
Run the latest Greenplum Command Center installer for the target VMware Greenplum system.
- Choose an installation path that is different from any existing Command Center instances.
- Choose a name for the Command Center installation that is different from any existing Command Center instances.
- Choose a Command Center web server port number that is different from any existing Command Center instances.
When the installation has finished source the gpcc_path.sh file in the new Command Center installation directory.
Edit the $GPCC_HOME/conf/app.conf file.
- Change the rpc_port parameter from the default value, 8899, to a different, available port number.
- Change the ws_perf_port parameter from the default value, 6162, to a different, available port number.
- Change the agent_perf_port parameter from the default value, 6163, to a different, available port number.

Before you start or stop a Command Center instance, be sure to source the greenplum_path.sh file in the VMware Greenplum installation directory and the gpcc_path.sh file in the corresponding Command Center installation directory. Then you can run the gpcc start, gpcc stop, or other gpcc commands.

Prepare the Standby Coordinator Host

After the Command Center software is installed, you start the Command Center web server and backend on the coordinator host or the standby coordinator host. Running Command Center on the coordinator host is recommended, but preparing the standby host ensures the standby can run Command Center if the coordinator fails.

Copy the .pgpass file from the coordinator host to the standby coordinator host. Run these commands from the coordinator:
```
$ ssh gpadmin@<standby_host>
$ scp gpadmin@<coordinator_host>:~/.pgpass ~
$ chmod 600 ~/.pgpass
```
Note: There are two alternative methods you can use to supply the gpmon user’s password so that you do not have to put the .pgpass file on the host. Command Center only requires the gpmon password when you run gpcc start, gpcc stop, or gpcc status.
1. Set the PGPASSWORD environment variable before you run gpcc commands. Example:
```
$ PGPASSWORD=changeme gpcc status
```
2. Add the -W option to gpcc commands to have the command prompt you for the password. Example:
```
$ gpcc start -W
```
If the Greenplum Command Center web server is to support TLS/SSL, a server certificate .pem file must be obtained and installed on the standby host in a location readable by the gpadmin user. The default path is /etc/ssl/certs/cert.pem.
If Greenplum Command Center is to support Kerberos authentication, VMware Greenplum must have Kerberos authentication set up and the required principals and keytabs must be installed on the standby host. See Enabling Authentication with Kerberos for Kerberos setup instructions. You can install Command Center without Kerberos authentication initially and then enable Kerberos later by running the gpcc krbenable command.

For more details on starting Command Center on the standby coordinator host, see the section Restarting Command Center After Coordinator Failure.