Is this at all possible?
I would to fetch and run docker image on X86. Add some things to it and then transfer that image to Docker on Raspberry Pi, which is a ARM plattform. Will this work?
I don’t think this is possible today because all of the binaries etc. bundled with the x86 image being specific to x86.
Even if I use an emty image as a base and build my own wordpress on it?
Can I somehow separate binaries of WordPress from html/css/etc files and the database and make this possible?
Like I put html files outside of container and mount into the container.
It might be possible through a pipeline of hacks but in general (at time of writing) I would advise you to docker build on ARM if you’re targeting ARM for a runtime. The one exception being if your program is something easily cross-compilable for another arch like Golang. However you specifically mention Wordpress here, which is going to require PHP, Apache etc. that run on ARM.
Hypriot might have some content that can help you get started: http://blog.hypriot.com/getting-started-with-docker-on-your-arm-device/
Yes I specifically want it for WP. I realise now that it will be quite difficult to achieve what I want. Found this article about persistent storage which perhaps is possible to use to store the WP data separate from the binaries and have two separate containers one one X86 and another on ARM and then just move the data from one to another.
But I think I will just stick on ARM with Hypriot if I manage to run WP on it. Thanks!