hobson@porthos.rutgers.edu (Kevin Hobson) (12/07/88)
Bare with me with my version of the English.
With all the discussion about dogfight, I would like to find
out what the program is using to talk to the machines.
There are 4 Silicon Graphics machines in our university. 3 are
owned by the Ceramics Department. The first time the technical
support person showed their system staff (graduates students) how to
play dogfight on two machines, one of our larger networks, went south.
Luckily, we isolate most departments from each other with gateways.
But in this case, 2 of our gateways were too busy routing packets
(broadcast packets) for this "game", that any other packets running to
these particularly gateways (5 subnets on each) were "stopped". We
found the machines within 5 minutes (HP Analyzer buffer filled in 1
second!!!). But this problem will happen again if someone starts up
this game. Our networking group can give advice but departments
can buy anything they want. We're limited to just telling them not to
run the program. But other departments might buy these machines and
leave it to students to administrate.
From what my boss, Ron Natalie, tells me, this particular
"game" broadcasts to find other candidates for the game. From what I
can see, the program is using some form of "sprayd". My advice to
others, isolated the Silicon Graphics machine (don't play) until they write a
proper network version.
My main problem is that our group is in a political situation
since we have little control over those machines. I cannot get help
from Silicon Graphics since their technical support department wants a
machine serial number. I already asked the students to ask about this
problem to the company but I haven't heard a response. I want to fix it
so it will work in proper fashion. Is there anyone out there with some
advice.
P.S. Ron wrote a TCP/IP version while he was a BRL. One machine
would run a deamon to which others would connect to play. It cut the
broadcasting business down to regular TCP/IP :-). Check with guys a
BRL for more information if you are interested.
--
Kevin Hobson Internet: hobson@rutgers.edu
Rutgers-The State University UUCP: {backbone}!rutgers!hobson
P.O. Box 879, CCIS BITNET: hobson@{cancer,pisces},
Hill Center, Busch Campus 1014025@rutvm1
Piscataway, N.J. 08855-0879 PHONE: (201) 932-2351mace@lum.SGI.COM (Rob Mace) (12/08/88)
In article <Dec.7.04.17.59.1988.25325@porthos.rutgers.edu>, hobson@porthos.rutgers.edu (Kevin Hobson) writes: > With all the discussion about dogfight, I would like to find > out what the program is using to talk to the machines. dog and arena currently use udp broadcast to communicate. Some machines can not handle large numbers of udpbroadcast packets. To do a udp broadcast there must be a line in the file /etc/services. By default this line is commented out. If you try to run dog without this line it prints the following message. |To run dog over the network you must have the following line |in your /etc/services file. | |sgi-dogfight 5130/udp # dogfight demo | |WARNING some machines can not handle large numbers of udp |broadcast packets. If you have machines from other vendors |on your network, running dog on your network may bring them |to a halt. VAXes are known to have this problem. Gateways will not transmit udp broadcast packets so you can isolate your other machines by using a gateway. Rob Mace Silicon Graphics