[sdnog] using RIPE atlas to check which DNS root your resolver prefers.

[Hiba Eltigani]

Thanks for sharing. The Ethionet seems really odd but I guess since the
e.root is hosted in the IXP, most probably the ISP is tagging all the
routes with no-advertise community to prevent them from going to the
Internet. I think it is a good practice to keep routes received from IXP
inside your network but may be root servers can be the exception ;).
BR

Hiba
On Dec 27, 2014 5:57 PM, "Nishal Goburdhan" <nishal at controlfreak.co.za>
wrote:
>
>
> some of you may remember me showing some graphs from the RIPE atlas
probes, showing DNS performance.  we've distributed several probes in
sudan, and i thought it would be interesting for you to see what these can
show you about the networks that the probes are attached to.
>
> if you look at:  https://atlas.ripe.net/contrib/root_anycast.html?msm_id=1
and choose "e.root" and "IPv4", you'll see that all the results for the
probes in sudan, report KRT.  that's good;  it tells us that from the
different network operators that have probes installed, DNS responses to
e.root goes "local" to khartoum.  this is what we want!
>
> in looking at this map, i noticed some oddities;  for example, if you
look at the probes in ethiopia, you'll see a response for SDB;  which is a
location in cape town.  so DNS resolution for the probes in those ethiopian
networks, goes all the way to cape town.  that's clearly not very optimal.
> what's likely happening, is that ethiopia telecom, buys IP transit from
seacom, who also buy transit from a south african ISP, who advertises the
e.root prefix to seacom.  seacom then route down to south africa to what
they believe to be the closest e.root.
>
> i call this odd, since, at least one sudanese operator is selling IP
transit to ethio telecom, so i would expect the ethio telecom probe to also
pickup the e.root from khartoum.  perhaps if the operator is here, and
listening, they can look into this  ;-)
>

> you can have a lot more fun (and learn a lot more about how things route
across the 'net, using the RIPE atlas probes.  you'll see that there aren't
a lot of probes installed in sudan;  it would be really good to get this
from as many (network) locations  as possible.  so if you want to help host
a probe, please ping me (or sara) off-list.
>
> --n.
> _______________________________________________
> Sdnog mailing list
> Sdnog at sdnog.sd
> http://lists.sdnog.sd/mailman/listinfo/sdnog
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.sdnog.sd/pipermail/sdnog/attachments/20141227/4f550681/attachment.html>