[SOLVED]Moving from 32-bit to 64-bit - not so hard after all

Hi Folks.
The time has come when I have to finally move from 32-bit to 64-bit, as I need to use docker and there isn't a 32-bit version of it.
Now, we all know that there isn't an out-of-the-box upgrade to do this. I've been running on 64-bit hardware for years but haven't wanted to go through the pain of trying to find the things I forgot to install for the new architecture.
I'm going to copy /etc somewhere so that I don't lose all the customisations that have been built up over time but the question is, can I generate a file listing all the packages that I currently have installed so that I can diff this with what I end up with under 64-bit and thereby work out what I forgot?
There are some things that I've built and installed from source but I suspect many are now in the package library, and the rest I can deal with as and when I need them.
I'm presuming (naively?) that VirtualBox will make the change transparent to all my virtual machines.
Anything else I've forgotten?
All the best,
Mark
The time has come when I have to finally move from 32-bit to 64-bit, as I need to use docker and there isn't a 32-bit version of it.
Now, we all know that there isn't an out-of-the-box upgrade to do this. I've been running on 64-bit hardware for years but haven't wanted to go through the pain of trying to find the things I forgot to install for the new architecture.
I'm going to copy /etc somewhere so that I don't lose all the customisations that have been built up over time but the question is, can I generate a file listing all the packages that I currently have installed so that I can diff this with what I end up with under 64-bit and thereby work out what I forgot?
There are some things that I've built and installed from source but I suspect many are now in the package library, and the rest I can deal with as and when I need them.
I'm presuming (naively?) that VirtualBox will make the change transparent to all my virtual machines.
Anything else I've forgotten?
All the best,
Mark