Advanced troubleshooting with nsenter
Let's start with a dramatic sentence: troubleshooting issues at runtime can sometimes be complex.
Also, understanding and troubleshooting runtime issues inside a container implies an understanding of how containers work in GNU/Linux. We explained these concepts in Chapter 1, Introduction to Container Technology.
Sometimes, troubleshooting can be very easy and, as stated in the previous sections, the usage of basic commands, such as podman logs, podman inspect, and podman exec, along with the usage of tailored health checks, can help us to gain access to the necessary information to complete our analysis successfully.
Images nowadays tend to be as small as possible. What happens when we need more specialized troubleshooting tools, and they are not available inside the image? You could think to exec a shell process inside the container and install the missing tool but sometimes (and this is a growing security pattern), package managers...