After successfully upgrading the kernel version of the operating system that is used to run customer containers as part of the Docker executor on CircleCI, CircleCI will be upgrading the full underlying operating system for jobs that use the Docker executor starting December 7, 2021. This change is critical to ensuring the underlying infrastructure that runs your jobs continues to provide reliable and performant execution.
This upgrade should be effectively invisible to customers. The current operating system version used is Ubuntu 18.04 and it will be upgraded to Ubuntu 20.04.
CircleCI is gradually rolling out this change for all Docker executor customers beginning on December 7, 2021.
- CircleCI does not expect this to be a breaking change for the overwhelming majority of Docker executor jobs as the jobs are isolated in their own containers.
- As part of this upgrade, the underlying kernel will be changing from 5.4 to 5.11
- If there are other issues observed as a result of this change, please comment on this post immediately so they can be analyzed and addressed.
- It is possible to view which kernel and operating system versions a job uses during execution by outputting “ uname -r”
- This upgrade will not impact Remote Docker jobs
Please comment on this post or reach out to your support contact if there are any questions about this change. Thank you!