»RHEL Requirements for Terraform Enterprise
When installing Terraform Enterprise on RedHat Enterprise Linux (RHEL), ensure you meet the following requirements.
- A supported version of RedHat Enterprise Linux.
- A supported Docker Engine configuration.
- We recommend installing the latest available version of Docker CE for CentOS. This is what is used for internal testing.
»When I run the installer, it allows me to download and install Docker CE on RedHat. Can I use that?
Yes, this is the recommended option. Docker CE is compatible with Terraform Enterprise, and tested nightly. It is not directly supported by RedHat, but there is a robust open source community.
»Can I use the Docker version in the RHEL Extras Repository?
Yes, if you are running Red Hat Enterprise Linux v7. If you are running v7 and choose to run Docker from the Extra Packages for Enterprise Linux (EPEL) repository, you must modify the default
»How can I prevent accidental upgrades of Docker?
To pin the version of Docker and prevent an inadvertent upgrade, follow this guide from RedHat.
Red Hat Enterprise Linux v8 does not offer docker in the EPEL repository, please use Docker CE for CentOS. This is tested nightly and ahead of each release of Terraform Enterprise.
»Docker was accidentally upgraded, how can I downgrade?
You can use the
yum downgrade command to downgrade the version of Docker that is installed, if it was installed from the EPEL repository.
For example, to downgrade from
docker-1.13.1-72.git6f36bd4el8.x86_64 stop the Docker service and execute the following.
sudo yum downgrade docker-1.13.1-72.git6f36bd4el7.x86_64 docker-client-1.13.1-72.git6f36bd4el7.x86_64 docker-common-1.13.1-72.git6f36bd4el7.x86_64 docker-rhel-push-plugin-1.13.1-72.git6f36bd4el7.x86_64
Afterwards, restart the Docker service and verify the newly installed version using
»Which storage driver should I use?
overlay2 storage driver.
»Can an installation where
docker info says that I’m using devicemapper with a loopback file work?
No. This is an installation that docker provides as sample and is not supported by Terraform Enterprise due to the significant instability in it. Docker themselves do not suggest using this mode.
»How do I know if an installation is in devicemapper loopback mode?
Run the command
sudo docker info | grep dev/loop. If there is any output, you’re in devicemapper loopback mode. Docker may also print warning about loopback mode when you run the above command, which is another indicator.