Deploying EDB Postgres Distributed using Trusted Postgres Architect v5

The standard way of automatically deploying EDB Postgres Distributed in a self-managed setting is to use EDB's deployment tool: Trusted Postgres Architect (TPA). This applies to physical and virtual machines, both self-hosted and in the cloud (EC2),

Get started with TPA and PGD quickly

If you want to experiment with a local deployment as quickly as possible, you can deploying an EDB Postgres Distributed example cluster on Docker to configure, provision, and deploy a PGD 5 Always-On cluster on Docker.

If deploying to the cloud is your aim, you can deploying an EDB Postgres Distributed example cluster on AWS to get a PGD 5 cluster on your own Amazon account.

If you want to run on your own Linux systems or VMs, you can use also use TPA to deploy EDB Postgres Distributed directly to your own Linux hosts

Prerequisite: Install TPA

Before you can use TPA to deploy PGD, you must install TPA. Follow the installation instructions in the Trusted Postgres Architect documentation before continuing.

Configure

The tpaexec configure command generates a simple YAML configuration file to describe a cluster, based on the options you select. The configuration is ready for immediate use, and you can modify it to better suit your needs. Editing the configuration file is the usual way to make any configuration changes to your cluster both before and after it's created.

The syntax is:

tpaexec configure <cluster_dir> --architecture <architecture_name> [options]

The available configuration options include:

FlagsDescription
--architectureRequired. Set to PGD-Always-ON for EDB Postgres Distributed deployments.
–-postgresql <version>
or
--edb-postgres-advanced <version>
or
--edb-postgres-extended <version>
Required. Specifies the distribution and version of Postgres to use. For more details, see Cluster configuration: Postgres flavour and version.
--redwood or --no-redwoodRequired when --edb-postgres-advanced flag is present. Specifies whether Oracle database compatibility features are desired.
--location-names l1 l2 l3Required. Specifies the names of the locations to deploy PGD to.
--data-nodes-per-location NSpecifies the number of data nodes per location. Default is 3.
--add-witness-node-per-locationFor an even number of data nodes per location, adds witness nodes to allow for local consensus. Enabled by default for 2 data node locations.
--add-proxy-nodes-per-locationWhether to separate PGD proxies from data nodes and how many to configure. By default one proxy is configured and cohosted for each data node.
--pgd-proxy-routing global|localWhether PGD Proxy routing is handled on a global or local (per-location) basis.
--add-witness-only-location locDesignates one of the cluster locations as witness-only (no data nodes are present in that location).
--enable-camoSets up a CAMO pair in each location. Works only with 2 data nodes per location.

More configuration options are listed in the TPA documentation for PGD-Always-ON.

For example:

[tpa]$ tpaexec configure ~/clusters/speedy \
         --architecture PGD-Always-ON \
         --platform aws \
         --edb-postgres-advanced 15 \
         --redwood \
         --location-names eu-west-1 eu-north-1 eu-central-1 \
         --data-nodes-per-location 3 \
         --pgd-proxy-routing global

The first argument must be the cluster directory, for example, speedy or ~/clusters/speedy. (The cluster is named speedy in both cases.) We recommend that you keep all your clusters in a common directory, for example, ~/clusters. The next argument must be --architecture to select an architecture, followed by options.

The command creates a directory named ~/clusters/speedy and generates a configuration file named config.yml that follows the layout of the PGD-Always-ON architecture. You can use the tpaexec configure --architecture PGD-Always-ON --help command to see the values that are supported for the configuration options in this architecture.

In the example, the options select:

  • An AWS deployment (--platform aws)
  • EDB Postgres Advanced Server, version 15 and Oracle compatibility (--edb-postgres-advanced 15 and --redwood)
  • Three locations (--location-names eu-west-1 eu-north-1 eu-central-1)
  • Three data nodes at each location (--data-nodes-per-location 3)
  • Proxy routing policy of global (--pgd-proxy-routing global)

Common configuration options

Other configuration options include the following.

Owner

Every cluster must be directly traceable to a person responsible for the provisioned resources.

By default, a cluster is tagged as being owned by the login name of the user running tpaexec provision. If this name doesn't identify a person (for example, postgres, ec2-user), you must specify --owner SomeId to set an identifiable owner.

You can use your initials, "Firstname Lastname", or any text that identifies you uniquely.

Platform options

The default value for --platform is aws, which is the platform supported by the PGD-Always-ON architecture.

Specify --region to specify any existing AWS region that you have access to and that allows you to create the required number of instances. The default region is eu-west-1.

Specify --instance-type with any valid instance type for AWS. The default is t3.micro.

Subnet selection

By default, each cluster is assigned a random /28 subnet under 10.33/16. However, depending on the architecture, there can be one or more subnets, and each subnet can be anywhere between a /24 and a /29.

Specify --subnet to use a particular subnet, for example, --subnet 192.0.2.128/27.

Disk space

Specify --root-volume-size to set the size of the root volume in GB, for example, --root-volume-size 64. The default is 16GB. Depending on the image used to create instances, there might be a minimum size for the root volume.

For architectures that support separate Postgres and Barman volumes:

  • Specify --postgres-volume-size to set the size of the Postgres volume in GB. The default is 16GB.

  • Specify --barman-volume-size to set the size of the Barman volume in GB. The default is 32GB.

Distribution

Specify --os or --distribution to specify the OS to use on the cluster's instances. The value is case sensitive.

The selected platform determines the distributions that are available and the one that's used by default. For more details, see tpaexec info platforms/<platformname>.

In general, you can use Debian, RedHat, and Ubuntu to select TPA images that have Postgres and other software preinstalled (to reduce deployment times). To use stock distribution images instead, append -minimal to the value, for example, --distribution Debian-minimal.

Repositories

When using TPA to deploy PDG 5 and later, TPA selects repositories from EDB Repos 2.0. All software is sourced from these repositories.

To use EDB Repos 2.0, you must use export EDB_SUBSCRIPTION_TOKEN=xxx before you run tpaexec. You can get your subscription token from the web interface.

Optionally, use --edb-repositories repository … to specify EDB repositories in addition to the default repository to install on each instance.

Software versions

By default, TPA uses the latest major version of Postgres. Specify --postgres-version to install an earlier supported major version, or specify both version and distribution using one of the flags described under Configure.

By default, TPA installs the latest version of every package, which is usually the desired behavior. However, in some testing scenarios, you might need to select specific package versions. For example:

--postgres-package-version 10.4-2.pgdg90+1
--repmgr-package-version 4.0.5-1.pgdg90+1
--barman-package-version 2.4-1.pgdg90+1
--pglogical-package-version '2.2.0*'
--bdr-package-version '3.0.2*'
--pgbouncer-package-version '1.8*'

Specify --extra-packages or --extra-postgres-packages to install more packages. The former lists packages to install along with system packages. The latter lists packages to install later along with Postgres packages. (If you mention packages that depend on Postgres in the former list, the installation fails because Postgres isn't yet installed.) The arguments are passed on to the package manager for installation without any modifications.

The --extra-optional-packages option behaves like --extra-packages, but it's not an error if the named packages can't be installed.

Hostnames

By default, tpaexec configure randomly selects as many hostnames as it needs from a preapproved list of several dozen names, which is enough for most clusters.

Specify --hostnames-from to select names from a different list, for example, if you need more names than are available in the supplied list. The file must contain one hostname per line.

Specify --hostnames-pattern to restrict hostnames to those matching the egrep-syntax pattern. If you choose to do this, you must ensure that the pattern matches only valid hostnames ([a-zA-Z0-9-]) and finds enough of them.

Locations

By default, tpaexec configure uses the names first, second, and so on for any locations used by the selected architecture.

Specify --location-names to provide more meaningful names for each location.

Provision

The tpaexec provision command creates instances and other resources required by the cluster. The details of the process depend on the architecture (for example, PGD-Always-ON) and platform (for example, AWS) that you selected while configuring the cluster.

For example, given AWS access with the necessary privileges, TPA provisions EC2 instances, VPCs, subnets, routing tables, internet gateways, security groups, EBS volumes, elastic IPs, and so on.

You can also provision existing servers by selecting the bare platform and providing connection details. Whether these are bare metal servers or those provisioned separately on a cloud platform, they can be used as if they had been created by TPA.

You aren't restricted to a single platform. You can spread your cluster out across some AWS instances in multiple regions and some on-premise servers or servers in other data centres, as needed.

At the end of the provisioning stage, you will have the required number of instances with the basic operating system installed, which TPA can access using SSH (with sudo to root).

Deploy

The tpaexec deploy command installs and configures Postgres and other software on the provisioned servers. TPA can create the servers, but it doesn't matter who created them so long as SSH and sudo access are available. This includes setting up replication, backups, and so on.

At the end of the deployment stage, EDB Postgres Distributed is up and running.

Test

The tpaexec test command executes various architecture and platform-specific tests against the deployed cluster to ensure that it's working as expected.

At the end of the testing stage, you have a fully functioning cluster.

For more information, see Trusted Postgres Architect.