"guix offload test" gets stuck with no output.

[Matthew Brooks]

I'm trying to get my desktop computer to do the actual building, since my 
laptop is fairly low spec.

I think I've gotten everything set up (following the directions at 
"https://www.gnu.org/software/guix/manual/html_node/Daemon-Offload-Setup.html";),
 but when I run "guix offload test", it just outputs the following, and then 
does nothing and never exits:

>guix offload: testing 1 build machines defined in '/etc/guix/machines.scm'...
>guix offload: '<ip address redacted>' is running guile (GNU Guile) 2.2.3

I've let it run for over an hour, and it doesn't output anything else, nor does 
it exit. I've checked the build machine, and it doesn't appear to be doing 
anything either (judging from checking the processes in "top").

My laptop (which is trying to offload the builds) is running GuixSD, and guix 
is version "c24b15472baaa7ec67d48cbf296bbe5ab727b78f" (a few days old).

My desktop (which I want to do the actual building) is running Ubuntu 18.04, 
and has guix installed on it following the instructions from 
"https://www.gnu.org/software/guix/manual/html_node/Binary-Installation.html";, 
and is running guix version "b494bbe466419dcac9f415c1152131f012b9555e" (updated 
a few hours ago).