Installing the LightDB-A Database Software

Describes how to install the LightDB-A Database software binaries on all of the hosts that will comprise your LightDB-A Database system, how to enable passwordless SSH for the gpadmin user, and how to verify the installation.

Perform the following tasks in order:

  1. Install LightDB-A Database:
  2. Enabling Passwordless SSH
  3. Confirm the software installation.
  4. Next Steps

Parent topic: Installing and Upgrading LightDB-A

Installing LightDB-A Database

You must install LightDB-A Database on each host machine of the LightDB-A Database system.

VMware distributes the LightDB-A Database software as a downloadable package that you install on each host system with the operating system’s package management system.

Open source LightDB-A Database releases are available as: source code tarballs, RPM installers for CentOS, and DEB packages for Debian and Ubuntu. See https://greenplum.org/download/ for links to source code and instructions to compile LightDB-A Database from source, and for links to download pre-built binaries in RPM and DEB format. For the Ubuntu operating system, LightDB-A also offers a binary that can be installed via the apt-get command with the Ubuntu Personal Package Archive system.

Downloading the LightDB-A Database Server Software (VMware LightDB-A)

You can download the LightDB-A Database Server software package from VMware Tanzu Network.

Be sure to note the name and the file system location of the downloaded file.

Verifying the LightDB-A Database Software (VMware LightDB-A)

VMware generates a SHA256 fingerprint for each LightDB-A Database software download available from Tanzu Network. This fingerprint enables you to verify that your downloaded file is unaltered from the original.

Follow the instructions in Verifying the VMware LightDB-A Software Download to verify the integrity of the LightDB-A Database Server software.

Installing the LightDB-A Database Software

Before you begin installing LightDB-A Database, be sure you have completed the steps in Configuring Your Systems to configure each of the coordinator, standby coordinator, and segment host machines for LightDB-A Database.

Important After installing LightDB-A Database, you must set LightDB-A Database environment variables. See Setting LightDB-A Environment Variables.

See Example Ansible Playbook for an example script that shows how you can automate creating the gpadmin user and installing the LightDB-A Database.

Follow these instructions to install LightDB-A Database from a pre-built binary.

Important You require sudo or root user access to install from a pre-built RPM or DEB file.

  1. Download and copy the LightDB-A Database package to the gpadmin user’s home directory on the coordinator, standby coordinator, and every segment host machine. The distribution file name has the format greenplum-db-<version>-<platform>.rpm for RHEL, Oracle Linux, or Rocky Linux systems.

    Note For Oracle Linux or Rocky Linux installations, download and install the rhel8-x86_64distribution files.

  2. With sudo (or as root), install the LightDB-A Database package on each host machine using your system’s package manager software.

    • For RHEL/Oracle Linux/Rocky Linux systems, run the yum command:

      $ sudo yum install ./greenplum-db-<version>-<platform>.rpm

    • For Ubuntu systems, run the apt command:

      $ sudo apt install ./greenplum-db-<version>-<platform>.deb

    The yum or apt command automatically installs software dependencies, copies the LightDB-A Database software files into a version-specific directory under /usr/local, /usr/local/greenplum-db-<version>, and creates the symbolic link /usr/local/greenplum-db to the installation directory.

  3. Change the owner and group of the installed files to gpadmin:

    $ sudo chown -R gpadmin:gpadmin /usr/local/greenplum*
$ sudo chgrp -R gpadmin /usr/local/greenplum*

(Optional) Installing to a Non-Default Directory

On RHEL/CentOS systems, you can use the rpm command with the --prefix option to install LightDB-A Database to a non-default directory (instead of under /usr/local). Note, however, that using rpm does not automatically install LightDB-A Database dependencies; you must manually install dependencies to each host system.

Follow these instructions to install LightDB-A Database to a specific directory.

Important You require sudo or root user access to install from a pre-built RPM file.

  1. Download and copy the LightDB-A Database package to the gpadmin user’s home directory on the coordinator, standby coordinator, and every segment host machine. The distribution file name has the format greenplum-db-<version>-<platform>.rpm for RHEL systems, or greenplum-db-<version>-<platform>.deb for Ubuntu systems, where <platform> is similar to rhel8-x86_64 (Red Hat 8 64-bit).

  2. Manually install the LightDB-A Database dependencies to each host system:

    $ sudo yum install apr apr-util bash bzip2 curl krb5 libcurl libevent \
libxml2 libyaml zlib openldap openssh openssl openssl-libs perl readline rsync R sed tar zip

  3. Use rpm with the --prefix option to install the LightDB-A Database package to your chosen installation directory on each host machine:

    $ sudo rpm --install ./greenplum-db-<version>-<platform>.rpm --prefix=<directory>

    The rpm command copies the LightDB-A Database software files into a version-specific directory under your chosen <directory>, <directory>/greenplum-db-<version>, and creates the symbolic link <directory>/greenplum-db to the versioned directory.

  4. Change the owner and group of the installed files to gpadmin:

    $ sudo chown -R gpadmin:gpadmin <directory>/greenplum*

Note All example procedures in the LightDB-A Database documentation assume that you installed to the default directory, which is /usr/local. If you install to a non-default directory, substitute that directory for /usr/local.

If you install to a non-default directory using rpm, you will need to continue using rpm (and of yum) to perform minor version upgrades; these changes are covered in the upgrade documentation.

Enabling Passwordless SSH

The gpadmin user on each LightDB-A host must be able to SSH from any host in the cluster to any other host in the cluster without entering a password or passphrase (called “passwordless SSH”). If you enable passwordless SSH from the coordinator host to every other host in the cluster (“1-n passwordless SSH”), you can use the LightDB-A Database gpssh-exkeys command-line utility to enable passwordless SSH from every host to every other host (“n-n passwordless SSH”).

  1. Log in to the coordinator host as the gpadmin user.

  2. Source the path file in the LightDB-A Database installation directory.

    $ source /usr/local/greenplum-db-<version>/lightdb_a_path.sh

    Note Add the above source command to the gpadmin user’s .bashrc or other shell startup file so that the LightDB-A Database path and environment variables are set whenever you log in as gpadmin.

  3. Use the ssh-copy-id command to add the gpadmin user’s public key to the authorized_hosts SSH file on every other host in the cluster.

    $ ssh-copy-id scdw
$ ssh-copy-id sdw1
$ ssh-copy-id sdw2
$ ssh-copy-id sdw3
. . .

    This enables 1-n passwordless SSH. You will be prompted to enter the gpadmin user’s password for each host. If you have the sshpass command on your system, you can use a command like the following to avoid the prompt.

    $ SSHPASS=<password> sshpass -e ssh-copy-id scdw

  4. In the gpadmin home directory, create a file named hostfile_exkeys that has the machine configured host names and host addresses (interface names) for each host in your LightDB-A system (coordinator, standby coordinator, and segment hosts). Make sure there are no blank lines or extra spaces. Check the /etc/hosts file on your systems for the correct host names to use for your environment. For example, if you have a coordinator, standby coordinator, and three segment hosts with two unbonded network interfaces per host, your file would look something like this:

    cdw
cdw-1
cdw-2
scdw
scdw-1
scdw-2
sdw1
sdw1-1
sdw1-2
sdw2
sdw2-1
sdw2-2
sdw3
sdw3-1
sdw3-2

  5. Run the gpssh-exkeys utility with your hostfile_exkeys file to enable n-n passwordless SSH for the gpadmin user.

    $ gpssh-exkeys -f hostfile_exkeys

Confirming Your Installation

To make sure the LightDB-A software was installed and configured correctly, run the following confirmation steps from your LightDB-A coordinator host. If necessary, correct any problems before continuing on to the next task.

  1. Log in to the coordinator host as gpadmin:

    $ su - gpadmin

  2. Use the gpssh utility to see if you can log in to all hosts without a password prompt, and to confirm that the LightDB-A software was installed on all hosts. Use the hostfile_exkeys file you used to set up passwordless SSH. For example:

    $ gpssh -f hostfile_exkeys -e 'ls -l /usr/local/greenplum-db-<version>'

    If the installation was successful, you should be able to log in to all hosts without a password prompt. All hosts should show that they have the same contents in their installation directories, and that the directories are owned by the gpadmin user.

    If you are prompted for a password, run the following command to redo the ssh key exchange:

    $ gpssh-exkeys -f hostfile_exkeys

About Your LightDB-A Database Installation

  • lightdb_a_path.sh — This file contains the environment variables for LightDB-A Database. See Setting LightDB-A Environment Variables.
  • bin — This directory contains the LightDB-A Database management utilities. This directory also contains the PostgreSQL client and server programs, most of which are also used in LightDB-A Database.
  • docs/cli_help — This directory contains help files for LightDB-A Database command-line utilities.
  • docs/cli_help/gpconfigs — This directory contains sample gpinitsystem configuration files and host files that can be modified and used when installing and initializing a LightDB-A Database system.
  • ext — Bundled programs (such as Python) used by some LightDB-A Database utilities.
  • include — The C header files for LightDB-A Database.
  • lib — LightDB-A Database and PostgreSQL library files.
  • sbin — Supporting/Internal scripts and programs.
  • share — Shared files for LightDB-A Database.

Next Steps