Daily tip

How to display cgroups virtual file system hierarchies?

With the command $lssubsys -M

(you need the package libcgroup and libcgroup-tools installed)

Daily tip

Is it possible to access a service running in a docker container from Internet?

By default services running on a container are not accessible from outside, what you need to do, provided everything is configured correctly in terms of DNS, public IP and domain registration, is to publish a container port to the host as below.

#docker container run -d -p 80:80 apache

With the -d switch we run the container in background and
 -p container_port:host_port instructs the host to create a NAT rule to forward any request to the host port 80 to the internal container port 80.