Have you read apt-secure(8) manpage as the explanatory notice (N:) attached to the *warning* message says?
It explains why you see the *warnings*, that it is the propose of the switch to downgrade the *errors* to a *warning* (so that worked as intended) and it mentions how to configure that in sources.list – also hinting at "trusted". ** Changed in: apt (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1680261 Title: apt-secure ignoring allow-unauthenticated during apt-update To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/apt/+bug/1680261/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs