Connecting to debian without a password from a mac

Create an RSA pair on mac

ssh-keygen

save it somewhere if not the default place eg id_rsa_utm

copy the public file to debian

on mac: more id_rsa_utm

and save the output on Debian to:

vi ~/.ssh/authorized_keys

back on mac

edit ~/ssh/config

Host deb
  User debian
  IdentityFile ~/.ssh/id_rsa_utm
  IdentitiesOnly yes # see comment in answer below

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