» RHEL Requirements for Terraform Enterprise

When installing Terraform Enterprise on RedHat Enterprise Linux (RHEL), ensure your OS and Docker configuration meat the following requirements:

» Install Requirements

Note: Using docker-1.13.1-84.git07f3374.el7.x86_64 will result in an RPC error as well as 502 errors and inability to use the application.

» Pinning the Docker Version

If docker-1.13.1-84.git07f3374.el7.x86_64 is already installed, first run:

sudo yum downgrade docker docker-client docker-common docker-rhel-push-plugin

Then, restart Docker and ensure the installed version changes to 1.13.1-72.git6f36bd4el7.x86_64. To pin the version and prevent an inadvertent upgrade, follow this guidefrom RedHat.

» Mandatory Configuration

If you opt to use Docker from RHEL extras, then you must make a change to its default configuration to avoid hitting an out of memory bug.

  1. Open /usr/lib/systemd/system/docker.service
  2. Remove the line that contains --authorization-plugin=rhel-push-plugin
  3. Run systemctl daemon-reload && systemctl restart docker
  4. Run docker info 2> /dev/null | grep Authorization to verify that there are no authorization plugins active. If nothing is printed, your installation is properly configured. If anything is printed, please contact support for further assistance.


» Can I use the Docker version in rpm-extras?

Sure! Just be sure to have at least 1.13.1 and authorization plugins disabled.

» When I run the installer, it allows me to download and install Docker CE on RedHat. Can I use that?

Yes, Docker CE is compatible with the current installer. However, it is not directly supported by RedHat. You still need to be sure that the storage backend is configured properly as by default, Docker will be using devicemapper in loopback, an entirely unsupported mode.

» 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: https://docs.docker.com/storage/storagedriver/device-mapper-driver/#configure-loop-lvm-mode-for-testing

» 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.