Upgrading

Datomic Cloud is designed to minimize the pain of upgrades, allowing rolling upgrades with zero downtime in the Production topology. To plan and implement an upgrade, you need to

Know What Version You Are Running

To determine the DatomicCFTVersion a template is running:

  • Select the name of your system stack in the CloudFormation console
  • On the Outputs tab, find the value for the DatomicCFTVersion key.

Choose a Release

The releases page provides three resources that can help you decide when and how to upgrade:

  • The Critical Notices section contains critical notices for all users. You should always read this section.
  • The Release History table includes a summary column with a brief description of each release.
  • The Release Notes provide a comprehensive list of changes in each release.

You should not downgrade to older versions of Datomic Cloud.

Perform the Release

Before any upgrade, read the critical notices for all releases between your current release(s) and the release(s) you are upgrading to. These notices may override the generic instructions below.

The documentation for each release lists an upgrade type, Make sure you perform the correct type of upgrade, which can be one of

Compute Upgrade

If you have more than one compute group, you should upgrade all of them. Upgrade the primary compute group first and then upgrade your query groups. It is ok to upgrade the query groups in parallel.

To update a Compute Stack:

  • Open the CloudFormation console
  • Select your stack via the checkbox or radio button.
  • Click the "Actions" button and select "Update Stack"
  • Select "Specify an Amazon S3 template URL:" and enter the CloudFormation template URL for the version that you wish to upgrade to (see Release page for all versions) then click "Next".
  • On the "Specify Details" screen, leave all options unchanged.
  • On the "Options" screen, leave all options unchanged.
  • On the "Review" screen, click the checkbox stating "I acknowledge that AWS CloudFormation might create IAM resources with custom names."

Storage Upgrade

To update your Storage Resources:

  • Open the CloudFormation console
  • Select your stack via the checkbox or radio button.
  • Click the "Actions" button and select "Update Stack"
  • Select "Specify an Amazon S3 template URL:" and enter the CloudFormation template URL for the version you wish to upgrade to (see Release page for all versions) then click "Next".
  • On the "Specify Details" screen, set the "Reuse Existing Storage" option to true:

    reuse-existing-storage-true.png

  • On the "Options" screen, leave all options unchanged.
  • On the "Review" screen, click the checkbox stating "I acknowledge that AWS CloudFormation might create IAM resources with custom names" and click "Update".

Storage and Compute Upgrade

To upgrade storage and compute:

Do Not Downgrade

Generally speaking, you should never downgrade Datomic CloudFormation templates.

  • Newer versions are better: they may contain important fixes.
  • Newer versions are compatible: they continue to support the entirety of the API.
  • Older versions may be incapable of correctly handling newer features.
  • Our support team is better able to help if you are running a recent version.

If you have a need to downgrade Datomic, please contact support first, and let us advise you.