Limited Visibility

[Geoff Austin]

On Tue, 2004-01-27 at 21:05, Stephane Bortzmeyer wrote:

> You only have two nameservers and they are in the same room. Not only
> it is poor redundancy (imagine a power failure in the building), but
> it also makes you very vulnerable to IP routing problems.
> 
> All your nameservers are in the same autonomous system (13037) and,
> much worse, in the same subnet (82.68.177.88/29). 
> 
> Since you are a customer of a recent /8 prefix (82.0.0.0/8), you may
> experience old and unmaintained BGP filters. Or there is simply a
> stupid routing problem which includes your prefix. You may use BGP
> looking glasses <URL:http://www.traceroute.org/> to see your route
> from the ISP which have the problem. 
> 
> But the best solution is probably to have nameservers in different
> locations.

Stephane, thanks for responding.

Clearly having both in the same location is far from ideal, but I had
only considered the resilience angle and not the routing one. 

Today I tried to reach the www server from one of the failing ISPs and
it could not find the site with www.w-sys.co.uk. However, when I enter
the numeric IP addess, i.e. 82.68.177.92, it displays the page happily.

Does this indicate that there is no routing problem, or is it more
subtle than that?