I have a def file which I'm attempting to use to build a singularity container on a host ubuntu 21.10 system. The lines I'm having trouble with are these
gpg --keyserver hkp://keyserver.ubuntu.com:80 --recv-key "shortnumber"
gpg -a --export "longernumber" | apt-key add -
Where do I go to find the correct keys to replace "shortnumber" and "longernumber" with? I've attempted to create these keys, and publish one at keyserver.ubuntu.com but still do not have it correct. I get this error
gpg: WARNING: nothing exported
Warning: apt-key is deprecated. Manage keyring files in trusted.gpg.d instead (see apt-key(8)).
gpg: no valid OpenPGP data found.
Thx. J