On Tue, 7 Apr 2026, at 10:32, Miroslav Lachman wrote:
> On 26/03/2026 15:56, Sean Eric Fagan wrote:
>> I’d asked Mark about this and he suggested I bring it up on the list:
>>
>> Has anyone thought about implementing controls / tunables to bhyve to
>> introduce errors? I am, most specifically right now, thinking about causing
>> disk I/O errors, or having requests dropped by the "hardware," to test error
>> handling.
>>
>> Last time I looked at the bhyve source code, it scared me, so if someone
>> else has looked at this, I’m love to know.
>
> I understand it would be nice to have it directly as a part of bhyve,
> but if you need something right now, you can try "gnop".
> See man gnop(8):
> Its main purpose is testing other GEOM classes, as it allows
> forced provider removal and I/O error simulation with a given
> probability.
>
> Or maybe someone with skill can reuse its code for bhyve feature.
>
> Kind regards
> Miroslav Lachman
Chuck Tuffli already did some work in this area:
https://papers.freebsd.org/2019/bsdcan/tuffli-frankensteins_disk_drive/
https://bhyvecon.org/bhyveconOttawa2019-Chuck.pdf
You should be able to find the related videos for these.
A+
Dave
