Needs to generate a unique ID for Docker

[juanbretti]

One way to generate a unique ID on a Docker, is to get the first ethernet MAC address.
Here is more information: https://stackoverflow.com/a/48651560/3780957.
The MAC address is stored in this file: cat /sys/class/net/eth0/address

[ezekg]

A MAC address is not a constant value. It can change depending on many factors, such as ISP or simply your current network device (wired vs WiFi), so I don’t think it should be relied upon.

[juanbretti]

Thank you @ezekg for your feedback.
I agree with you that MAC Addresses are not constant values.

Notice the idea of using the MAC Address is third in the case of Linux systems. It is proposed as fail-safe.

All the previously used values, for example /etc/machine-id could be changed as well. For example StackOverFlow
As you mentioned, similar could happen with the proposed ethernet address /sys/class/net/eth0/address, here StackOverFlow

But I think a solution should be found for Dockers.
Maybe pulling the container ID from the running container?

[ezekg]

Hey @juanbretti, sorry for the late response. There's some discussion on Docker containers here. That discussion talks about using cgroup to obtain a unique container ID. The big problem with using a MAC address is that it can change randomly (ISP, WiFi/wired, etc.), without any explicit action from the end user.

Feel free to open another PR that does something with cgroup within a Docker container.