Charmed PostgreSQL K8s

Channel Revision Published Runs on
latest/stable 20 20 Sep 2022
Ubuntu 20.04
14/stable 73 18 Apr 2023
Ubuntu 22.04
14/candidate 139 19 Sep 2023
14/beta 145 26 Sep 2023
14/edge 148 Yesterday
juju deploy postgresql-k8s --channel 14/stable
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Charm types “legacy” vs “modern”

There are two types of charms stored under the same charm name postgresql-k8s:

  1. Reactive charm in the channel latest/stable (called legacy)
  2. Ops-based charm in the channel 14/stable (called modern)

The legacy charm provided endpoints db and db-admin (for the interface pgsql). The modern charm provides old endpoints as well + new endpoint database (for the interface postgresql_client). Read more details about the available endpoints/interfaces.

Note: Please choose one endpoint to use. No need to relate all of them simultaneously!

The default track “latest” vs “14”

The default track has been switched from the latest to 14 for both VM and K8s PostgreSQL charms. It is to ensure all new deployments use a modern codebase. We strongly advise against using the latest track due to its implicit nature. In doing so, a future charm upgrade may result in a PostgreSQL version incompatible with an integrated application. Track 14 guarantees PostgreSQL 14 deployment only. The track latest will be closed after all applications migrated from Reactive to Ops-based charm.

How to migrate from “legacy” to “modern” charm

The “modern” charm provides temporary support for the legacy interfaces:

  • quick try: relate the current application with new charm using endpoint db (set the channel to 14/stable). No extra changes necessary:
    charm: postgresql-k8s
    channel: 14/stable
    trust: true

Warning: NO in-place upgrades possible! Reactive charm cannot be upgraded to Operator-framework-based one. To move DB data, the second/modern DB application must be launched nearby and data should be copied from “legacy” application to the “modern” one. Canonical Data Platform team is preparing copy&paste guide right now. Please contact us if you need migration instructions.

Note: the trust option must be enabled if Role Based Access Control (RBAC) is in use on your Kubernetes.

How to deploy old “legacy” postgresql charm

Deploy the charm using the channel latest/stable:

    charm: postgresql-k8s
    channel: latest/stable

Note: remove Charm store prefix cs: from the bundle. Otherwise the modern charm will be chosen by Juju (due to the default track pointing to 14/stable and not latest/stable). The common error message is: cannot deploy application "postgresql": unknown option "...".

Config options supported by modern charm

The legacy charm config options were not moved to the modern charm due to no need. The modern charm applies the best possible configuration automatically. Feel free to contact us about the DB tuning/config options.

Extensions supported by modern charm

Please find the list of supported PostgreSQL Extensions by modern charm. Feel free to contact us with a list of required extensions.

Supported PostgreSQL versions by modern charm

At the moment, the modern charms support PostgreSQL 14 (based on Jammy/22.04 series) only. Please contact us if you need different versions/series.

Supported architectures: amd64, arm64, …

Currently, the charm supports architecture amd64 only. See the technical details in “Supported architectures”.

How to report issues and contact authors

The “legacy charm” (from latest/stable) is stored on Launchpad, here is the link to report all legacy charm issues.

The “modern charm” (from 14/stable) is stored on GitHub, here is the link to report modern charm issues.

Do you have questions? Contact us!

Help us improve this documentation

Most of this documentation can be collaboratively discussed and changed on the respective topic in the doc category of the Charmhub forum. See the documentation guidelines if you’d like to contribute.

Last updated 27 days ago. Help improve this document in the forum.