- [Instructor] The Docker Certified Associate exam blueprint
says that you should be prepared
to interpret errors related to installing Docker.
It's my hope that throughout this course,
you've gained some experience interpreting errors
and troubleshooting Docker.
And it's my recommendation that if you haven't already,
you gain some personal experience
through dealing with installation simply
by trying to install Docker on one
or more platforms that we've demonstrated
throughout the course.
Now that being said, I do have a few suggestions
of things to look for.
For example, common issues with Docker include
not having a compatible Linux kernel
with the version of Docker that you're trying
to run in Linux.
With so many different versions
and architectures of Linux, I know
that this can be confusing.
Also, you need to ensure that DNS
is properly configured.
Without properly-configured DNS,
you can run into a number of confusing issues.
And finally, ensure that the container
that you're trying to run is compatible
with the host operating system that you're trying
to run that container on.
So just keep that in that the container
that you're running must be compatible
with your host operating system.
And now let's go over to the command line,
where I've got some more common errors
that you should be aware of.
In my experience, one of the most common errors
that people run into after they install Docker
is not being able to run Docker commands
without being root.
The command to add yourself, your user account
in Linux to the Docker group, which would allow
you to run Docker commands using your own user account
is sudo usermod -aG docker, for the Docker group,
and then $USER to represent your user account.
That way, you can run Docker commands
as yourself without SUing to the root account.
Another common installation issue
that I have seen is the Docker daemon simply not running.
In most cases, the Docker daemon
is started automatically after installation,
but this can vary from platform to platform.
So the command that you need to know
to ensure that the Docker daemon is enabled
to start by default when the operating system boots up,
is sudo systemctl enable docker.
Another command that you need to know
is sudo systemctl start docker if for some reason
the Docker daemon isn't running at all.
For more information on troubleshooting Docker
installation issues, I encourage you
to check out the Docker documentation.