Bug#990069: openssh-server: Not accepting new connections during Debian 10 -> 11 upgrade

On Sat, Jun 19, 2021 at 12:53:48PM +0200, Olaf van der Spek wrote:
> During a Debian 10 -> 11 upgrade, the SSH server doesn't appear to be accepting new connections. IMO this is less than optimal, and not sure if this was always the case.
> Would it be possible to keep accepting connections, or at least to make the time window in which SSH is down as short as possible?

That's odd, because we already take care to do that.  Any chance of some
logs?  I think the most useful things would be /var/log/dpkg.log,
/var/log/apt/term.log, and the bits of "journalctl -b -u ssh.service"
that show when sshd stopped and started.