[comp.protocols.tcp-ip] Ping & debugging tools

jbvb@GAAK.LCS.MIT.EDU.UUCP (04/17/87)

We include a Ping in every copy we ship.  It is the tool of choice for
dealing with support calls of the form "... I tried telnet and it just
timed out...", because it bypasses a lot of higher-level problems:
ICMP doesn't care if the PC is in its host table, trailers don't get
involved because the packets are short, everything including gateways
ought to respond to it, etc.  Our Ping displays extensive network
statistics, and can act as a server, and in this mode, we have used it
to diagnose various customer problems caused by a crazed machine
(not ours) generating excessive broadcasts of one kind or another. 

Other debugging tools we find useful on a workstation include programs
for explicitly checking nameservers, displaying who responded to a
query and what they responded with.  For instance, as of Wednesday,
4/15, DCN1's IEN-116 UDP service was giving 128.6.4.7 for
MVS.RUTGERS.EDU, whose un-transposed address is 128.6.7.4.  I could
tell I was getting a bogus address using other programs, but I would
have had to read through a lot of debugging trace to find out who, and
it wouldn't have been presented in easy-to-read formats.

James B. VanBokkelen
FTP Software Inc.
jbvb@ai.ai.mit.edu

Mills@UDEL.EDU (04/17/87)

Jim,

Just to underscore your point, I confirmed your observation that the dcn1
name server was in fact bog, but using my own flashy toolkit. Geez, you
mean somebody is still using old-style name servers? Well, it turned out
the new-style (domain) name server on dcn1 is bogged as well. The bug
several years old, but was revealed only by your tests just now.

Dave