Release Notes

21.10.6 Release Notes

Tim Coleman  |  22 July 2022

We are pleased to announce the official release of EventStoreDB OSS & Commercial version 21.10.6 long term support (LTS).

This release contains an important dataloss bugfix and we strongly recommend that everyone running 21.10.x upgrade to this version. A new version of 20.10 will shortly be released with the same fix.

This LTS release will be supported until October 2023.

Read more about our versioning strategy here.

The complete changelog can be found here. If you need help planning your upgrade or want to discuss support, please contact us here.

EventStoreDB 21.10.6 is available for the following operating systems:

  • Windows
  • Ubuntu 18.04
  • Ubuntu 20.04
  • CentOS 7 (Commercial version)
  • Amazon Linux 2 (Commercial version)
  • Oracle Linux 7 (Commercial version)

Additionally, an experimental build for ARM64 processors will be available shortly as a Docker image.

Note: Ubuntu 16.04 is not supported anymore as of the 21.10.0 release, more information about Ubuntu’s release and support policy can be found here.

Where Can I Get the Packages?

Downloads are available on our website.

The packages can also be installed using the following instructions.

Ubuntu 18.04/20.04 (via packagecloud)

curl -s https://packagecloud.io/install/repositories/EventStore/EventStore-OSS/script.deb.sh | sudo bash

sudo apt-get install eventstore-oss=21.10.6

Windows (via Chocolatey)

choco install eventstore-oss -version 21.10.6

Docker (via docker hub)

docker pull eventstore/eventstore:21.10.6-focal

docker pull eventstore/eventstore:21.10.6-buster-slim

Highlights for this release

Dataloss fix: Use follower writer checkpoint for replication tracking (EventStore#3527)

Prior to this fix it was possible, if a leader changeover occurred under load, for the last event written on the leader to be lost. This was more likely to happen under high load and with large events. The cause was that the last event written on the leader could be acknowledged and appear in reads and subscriptions while it was still being replicated to the cluster, and therefore if the leader changed before the replication could complete the event would be removed from the old leader and lost.

Removed error: “Should never complete request twice” (EventStore#3525)

This error could appear during leader changeover but since 21.10.5 has not been an indication of a real problem.

Upgrade Procedure

To upgrade a cluster from 20.10.x or 21.10.x,  a usual rolling upgrade can be done:

  • Pick a node (start with follower nodes first, then choose the leader last).
  • Stop the node, upgrade it and start it.

There is no way to perform a rolling upgrade between version 5.x and version 21.10.x due to changes in the replication protocols and the way nodes gossip and host elections. 

As such, the upgrade process from 5.x is as follows:

  • Take down the cluster
  • Perform an in-place upgrade of the nodes, ensuring that the relevant configuration and certificates are set up
  • Bring the nodes back online and wait for them to stabilise

Documentation and previous releases notes

Documentation for EventStoreDB can be found here, and previous release notes can be found here.

Providing Feedback

If you encounter any issues, please don’t hesitate to open an issue on GitHub if there isn’t one already.

Additionally, there is a fairly active Discuss channel, and an #eventstore channel on the DDD-CQRS-ES Slack community.

If you have any questions that aren't covered in these release notes or the docs, please feel free to reach out.


Photo of Tim Coleman

Tim Coleman Tim is a Distributed Systems Engineer at Event Store with a background in Event Sourcing in the financial sector. He lives in Oxfordshire, UK and can be found on GitHub.