Efficacy of using short timeout values for an A record

[goran kent]

On Tue, Feb 14, 2012 at 7:01 PM, Oliver Garraux <oliver at g.garraux.net> wrote:
>> I need to setup an A record for a machine who's IP might change
>> unexpectedly, and I need to ensure PCs out there cache it for as short
>> a time as possible:
>>
>>    host1    300  IN A 10.10.10.10
>>
>> Does anyone know whether MS windows PCs will in fact honour that 300s,
>> then force a re-lookup?  Can I use even shorter values?  eg, 60?
...
> I don't think you'll have a problem with clients not respecting TTL's.
>  Some ISP's resolvers might have a minimum TTL, but 300 seconds isn't
> all that low.  You might run into issues with some service providers
> if you're trying to do something like a 5 second TTL.

Thanks to all for the spirited responses - it's appreciated.

All good information.

-- 
Regards,
gk