I was able to resolve it by following these steps in the readme in the CANopenLinux repository level.
Dear all, I hope I post this in the right spot. When I try to follow the https://canopennode.github.io/CANopenSocket/md_doc_gettingStarted.html tutorial but I fail to startup the canopend without the error message. I set up the virtual can and canopenend takes -s with an attribute but it does not offer -a as attribute and I wonder if this is the problem. -a is not listed as flag in the canopend --help list. What am I doing wrong? I assume the -a is not up-to-date anymore. Sincerely, Kelan