I have Jenkins running on an x86 processor, but recently setup a k8s cluster on some Raspberry pis that run arm.
Unfortunately the agents don't start due to an "container exec format error".
I'm not too sure but the pods that I create have two containers one is the main container and one is named jnlp. The jnlp defaults to using jenkins/inbound-agent:4.3-4. Unfortunately this image does not have an arm64 version available on docker hub, and it seems that kubernetes just pulls, probably the other linux/amd64 image in it's place I guess.
I couldn't figure out a way to actually tweak this in the UI anywhere (although I'm fairly new). I didn't see how I could override this, since the container is specified in a list and the yaml section says that it will just append things to the list, so the pod will never work.
I did dig into the source, found a reference to 4.3-4 and changed it to 4.10-2 (which does have images https://hub.docker.com/r/jenkins/inbound-agent/tags?page=1&ordering=last_updated&name=4.10-2 and the pod started), then manually updated the plugin.
I would recommend that the inbound agent image be updated, or arm and other architecture builds are created for the 4.3-4