» CentOS Requirements for Terraform Enterprise

When installing Terraform Enterprise on CentOS Linux, ensure your OS and Docker configuration meet the following requirements:

» Install Requirements

  • A supported version of CentOS.
  • A suitable version of Docker:
    • Docker 1.13.1 (available in the extras repository).
    • Docker CE version 17.06 through 19.03.8.
    • Docker EE version 17.06 through 19.03.8.
    • Or you can allow the installer to install Docker for you.
  • A properly configured docker storage backend, either:

    • Devicemapper configured for production usage, in accordance with the Docker documentation. This configuration requires a second block device available to the system to be used as a thin-pool for Docker. You may need to configure this block device before the host system is booted, depending on the hosting platform. Note: Current, Docker documentation states that the devicemapper storage driver is deprecated in Docker Engine 18.09 and will be removed in a future release. It is recommended that users of the devicemapper storage driver migrate to overlay2.
    • A system capable of using overlay2. The requires at least kernel version 3.10.0-693 and, if XFS is being used, the flag ftype=1. The full documentation on this configuration is on the Docker site.

If you choose to have Docker installed via the install script, ensure that /etc/docker/daemon.json is set up correctly, first. The installer's default configuration sets up the devicemapper driver to use a loopback file, which is explicitly not supported, and the installation script will fail. Setting up the driver for direct-lvm usage before installation will help ensure a successful installation.


» Can I use the Docker version in extras?

Sure! Just be sure to have at least 1.13.1.

» 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 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.