User FAQ

Where should I get Kubernetes?

This is covered by our getting-started guide.

We recommend you do not use binaries from http://storage.googleapis.com/kubernetes, as these are neither official releases nor maintained.

Command not found?

Kubernetes expects an argv array for the command. If you put your command and its arguments all in one string, that is interpreted as the command name. Put the arguments into separate array elements instead.

Use of environment variables on the command line

As discussed in Docker's documentation, the container's command is not necessarily executed in a shell, in which case environment variables are not expanded in command-line arguments. In particular, non-default commands are specified via Kubernetes's API using the array form of Docker's Cmd argument, which causes the command to be execed directly. You can cause environment variables to be evaluated by simply making your command a shell, with your application's command line as its argument. For example:

{ "command": [ "sh", "-c", "redis-server /etc/redis/redis.conf --slaveof $SERVICE_HOST $REDIS_MASTER_SERVICE_PORT"] }

Why can't my containers find the service they need to connect to?

You need to create the service before creating the pods that will connect to the service.

Also ensure you are using the correct environment variable names.

If neither of these is your problem, see the Debugging-FAQ.

How do I change the size of my cluster?

Change NUM_MINIONS in the platform-specific config-default.sh file, such as GCE's.

Currently, NUM_MINIONS needs to be changed before turning up the cluster.

How do I pull images from a private registry?

• For more recent versions of Kubernetes, create the registry service with a PortalIP address of your choice within the portal IP range, and use that IP address for the registry name
• For version 0.4 and older, see the answer on stackoverflow