Re: Deprecating RSA ssh host keys in 16

On 9/27/24 10:21, Ed Maste wrote:
> On Tue, 24 Sept 2024 at 14:41, Colin Percival <cperciva@tarsnap.com> wrote:
>> I don't think we should turn off RSA host key generation in general in
>> 15.x since for non-VM/cloud images the first boot time is less relevant
>> (if you're installing from an ISO image, the installer will take far
>> longer than the host key generation) but I think it would make sense to
>> deprecate RSA host keys in 15 and then turn them off by default in 16.
> 
> This might be overly conservative, and users who need RSA host keys
> can trivially enable them.
> 
> I'm also not fond of having different behaviour in a cloud environment
> vs when using the installer -- imagine a user with an old ssh client
> that has trouble connecting to FreeBSD servers, but only those hosted
> on EC2.

Wearing my release engineering hat: I don't like making changes like this
without warning, and we have a standard policy of "warn in N, gone in N+1"
so I figured we should follow that.

Wearing my EC2 maintainer hat: *In cloud environments* this is important
enough to diverge from normal practice; but the first-boot-key-generation
time is not relevant outside of clouds.

I agree that maintaining consistency is generally a good thing, but in this
case I think there are strong enough arguments on both sides to justify the
divergence.

-- 
Colin Percival
FreeBSD Release Engineering Lead & EC2 platform maintainer
Founder, Tarsnap | www.tarsnap.com | Online backups for the truly paranoid