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Re: [TCLUG:4236] ISP dropping packets



At 11:26 AM 2/18/99 -0600, you wrote:
>Is there a tool I can run on my Linux box that will evaluate that sort of
>thing.

For a large set of tools like this, look into nocol: it can monitor
specific port traffic (like a web server being swapped), your own network
traffic, and generic thru put to various hosts.

http://www.netplex-tech.com/software/nocol/

On the flip side, you could just employ traceroute and PERL... 8>

A side note:  it looks like the routers are having trouble (yesterday we
had similar problems with a lot of our routes..)  The various routers (incl
some that USWest employs) have been ... `known' .. to begin losing packets,
or atleast delaying them so severely that they look lost.  Sometimes a bug
condition is initiated and there is a memory leak, where there is less and
less memory available for packet work.  Other times, (common with some
ISPs) a bogus route table is propagated, either causing circular loops, or
focusing too much on a single router.  Finally, and not to be under
estimated, is the damage a smurf attack will do; kids love it.  (Smurf
attacks, in short flood the network with pings, usually to broadcast
address or made to return to a broadcast address, etc.  Besides creating a
lot of traffic, they may cause the routers to trip the various bugs I
mentioned earlier).

All the best,
Randy Maas
randym@acm.org