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Re: Apt + Netselect Server choosing

"Stephen J. Carpenter" <sjc@delphi.com> writes:

> > Hmm, those 50% thruput ones are interesting. I don't see that effect on my
> > network. Is your connectivity to those hosts really that bad?

This is likely a rate-limitting router that is intentionally dropping these
packets. That's assuming you aren't actually seeing any connectivity problems
while this happens.

> Well I have never heard of traceroute working...it always stops right at the 
> gateway:

I believe there's a modified version of traceroute out there that sends
different types of packets (TCP ACK packets i think?) that should elicit RST
packets from other hosts even through a remote firewall, though i'm not sure
it'll help if it's your own firewall.

The number of hops turns out to be a really insignificant metric though, the
total round trip time and bandwidth would be much more important. It would be
nice to see a bing-like calculation where you send icmp echo requests of
various sizes and calculate the total bandwidth available from each host. Raw
bandwidth should be more important than latency for archives anyways.

Also, for hosts behind a slow link, like a PPP link, the measurements can be
very inaccurate if netselect is given a large list. I imagine this is because
it saturates the link with hostname lookups and other traffic and that causes
subsequent measurements to be skewed. It would be nice to give it a
rate-limitting option to have it avoid saturating the link while doing these


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