I did this. What is a bit strange is that the error message seemingly randomly alters between what I already reported above and the following: mdj@hat:~/prusa$ guix offload test guix offload: testing 1 build machines defined in '/etc/guix/machines.scm'... guix offload: Guix is usable on 'wand.pdc.kth.se' (test returned "/gnu/store/883yjkl46dxw9mzykykmbs0yzwyxm17z-test") guix offload: 'wand.pdc.kth.se' is running GNU Guile 3.0.1 sending 1 store item (0 MiB) to 'wand.pdc.kth.se'... exporting path `/gnu/store/kw12ny565xl5p05ag6ysgshc9mhh4rz2-export-test' guix offload: error: unknown error while sending files over SSH This error message is more common. In this case, I couldn't see anything obviously strange except the following backtrace which contains strange characters: 31963 write(2, "Backtrace:\n 13 (apply-smob/1 #)\nIn ice-9/boot-9.scm:\n 718:2 12 (call-with-prompt (\"prompt\") # \342\200\246)\nIn ice-9/eval.scm:\n 619:8 11 (_ #(#(#)))\nIn ice-9/command-line.scm:\n 181:18 10 (_ #)\nIn unknown file:\n 9 (eval (begin (use-modules (guix) (srfi srfi-34) # #) \342\200\246) #)\nIn ice-9/eval.scm:\n 721:20 8 (primitive-eval (begin (use-modules (guix) (srfi \342\200\246) \342"..., 1150 I have also noticed that the above (the error message) happens inside the function send-files. It is the last error clause at the end of the function which reports the error message. I'd like to be able to, e.g., modify the function send-files to give some debugging output. How can I easily do that? Should I checkout guix with git and try to run it in the source tree? Or do you have other suggestions? Best regards, Mikael On Sat, Mar 21, 2020 at 11:16 PM Ludovic Courtès wrote: > Hi Mikael, > > Mikael Djurfeldt skribis: > > > I will look at the other buh reports. Meanwhile, do you have any hint on > > where to look/insert logging code in order to see what is going on? > > On ‘wand’, can you run something like: > > sudo strace -s 500 -p $(pidof sshd) -f -o sshd.log > > After that, run ‘guix offload test’ from the other host, and check what > ‘sshd.log’ contains. If would in particular look for all the ‘execve’ > syscalls as well as what happens right before ‘exit_group’ syscalls. > There are probably error messages lurking there. :-) > > You can share excerpts of the log but note that it will contain > sensitive crypto material, so beware. > > Thanks in advance, > Ludo’. >