Thanks for the report. I was able to reproduce this bug. Basically:
$ systemctl start ssh.socket $ ssh-keyscan localhost Interesting enough, I wasn't able to solve the problem by setting RuntimeDirectoryPreserve=yes. I edited sshd.service and added the directive there, but I still see the fatal errors on /var/log/auth.log. Maybe I'm missing something, but I don't have the time right now to dive deep into this. Marcin, as Seth said above, the right way to edit a systemd unit file is to invoke "systemctl edit", which will make sure that the new .service file is installed in a way that won't get ovewritten when you upgrade your package/system. You might want to use the "--full" option when invoking the command, which will already pre-fill the new file with the contents of the original .service. I'm marking this bug as Triaged and setting the priority to Medium. Hopefully someone will be able to work on it soon. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1905285 Title: socket-activated sshd breaks on concurrent connections To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/openssh/+bug/1905285/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs