prompt to update a host key

Nico Kadel-Garcia nkadel at
Sat Mar 16 11:40:08 AEDT 2019

On Thu, Mar 14, 2019 at 8:01 PM Josh Soref <jsoref at> wrote:
> Out of curiosity, why don't you just not store a host key for such systems?
> That's what we do:
> UserKnownHostsFile /dev/null
> Historically I would have been interested in such a thing, but I've long
> since given up.

You forgot "LogLevel Error" and "StrictHostKeyCheckng no" to
completely disable the use of $HOME/.ssh/known_hosts and make it shut

If the hosts I dealt with would have consistent IP addresses and DNS
tied to host keys, I'd say "this is a potential security risk".
However, I deal with multiple raw OS images deployed into
virtualization environments with DHCP randomized IP addresses,
regenerated multiple times a day, as a matter of course. The cost of
saying "flush another old key" all the time is burdensome. That much
extra work is actually anti-security.

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