How to determine if a process runs inside lxc/Docker?
The most reliable way is to check /proc/1/cgroup. It will tell you the control groups of the init process, and when you are not in a container, that will be / for all hierarchies. When you are inside a container, you will see the name of the anchor point. With LXC/Docker containers, it will be something like /lxc/<containerid> or /docker/<containerid> respectively.
Docker creates a .dockerenv file at the root of the directory tree inside container.You can run this script to verify
#!/bin/bashif [ -f /.dockerenv ]; then echo "I'm inside matrix ;(";else echo "I'm living in real world!";fiMORE:Ubuntu actually has a bash script: /bin/running-in-container and it actually can return the type of container it has been invoked in. Might be helpful.Don't know about other major distros though.