On Sat, 2014-04-12 at 14:09 +0800, P J P wrote:
> On Saturday, 12 April 2014 11:11 AM, William Brown wrote:
> Say I have freshly installed my fedora system at home. I then boot it up
> and start to use it. My laptop is caching DNS results all the while from
> the "unreliable" ISP.
> I then go to work and suddenly things don't work.
> Having a DNS cache doesn't fix your unreliable ISP: You need to lodge a
> complaint with your ISP.
What, no! that was the case for having local cache and not forwarding queries to the
ISP's name servers at all. Because those are not reliable.
> See my previous email, about flushing the cache on network change.
Yes I saw. About automatic cache clearance etc. I agree. Those are features to be
requested from the DNS software or maybe NM. I've been using 'dnscache'
without any trouble whatsoever.
Umm what? You cannot have your cake and eat it too.
If you flush the cache of interface route change, the entire point you
made about trying to no forward to an unreliable ISP is invalid.
Consider, I get home, and open my laptop. Cache is cleared, and I'm now
populating that cache with the contents from the ISP.
But if you weren't to clear the cache, I could be at home caching bad
records, then when I go to work they persist.
You cannot have both.
I would rather that cache is flushed on interface change as it prevents
so many more issues than making that cache last across potential network
At the end of the day, I cannot stress enough, if you have an ISP with
bad DNS caching or that is unreliable, you need to fault your ISP, it is
not an issue for the OS to solve.
William Brown <william(a)firstyear.id.au>