bruce@THINK.COM (05/05/89)
I was just debugging some routes from our Nearnet gw with the Cisco ping command, which allows one to turn on IP options like "record route". I began just pinging a friendly Sun4 at NRL (on 128.60) without any IP options on, and the machine was responding fine. But when I tried it with record-route on, it stopped responding to any pings for quite a while, even subsequent ones without record on. Since I can't seem to reach any machines on that net after the experiment, I assume the target machine didn't crash, but it seems as if I might be crashing a gateway along the way with record-route! I did this twice with the same results. I can reach that net again after about 10 minutes. If anyone had a couple of unexpected gateway crashes today, the last about 5pm, this could explain it. --Bruce Walker (Nemnich), Thinking Machines Corporation, Cambridge, MA bruce@think.com, think!bruce, bjn@mitvma.bitnet; +1 617 876 1111
vjs@rhyolite.SGI.COM (Vernon Schryver) (05/06/89)
In article <8905042139.AA01559@mozart.think.com>, bruce@THINK.COM writes: > I was just debugging some routes from our Nearnet gw with the Cisco ping > command, which allows one to turn on IP options like "record route". > > --Bruce Walker (Nemnich), Thinking Machines Corporation, Cambridge, MA > bruce@think.com, think!bruce, bjn@mitvma.bitnet; +1 617 876 1111 Using `ping -R` (derived from the BRL version) is entertaining and has been helpful to me in the continuing Butterfly wars. One can often infer which version of 4.xBSD networking a system is running by whether it ignores the RR option when it responds, or does not respond at all. Unfortunately, I know of only sgi.sgi.com and brl.mil which answer with routes. Would it be possible to compile a list of geograpically dispersed machines (modulo the network topology) which usefully answer Record-Route Echo-Requests? Traceroute is handy, but does not satisfy the same needs. Vernon Schryver Silicon Graphics vjs@sgi.com
evan@BRAZOS.RICE.EDU (Evan Wetstone) (05/06/89)
It has been our experience that sending an ICMP ECHO with IP options turned on through a Sun (SunOS 3.5 or lower, we haven't tested it with 4.0) that has two Ethernet interfaces will immediately crash the Sun. If anyone between you and NRL is using a Sun-3 with two interfaces, you probably crashed it with that ping..... Evan Wetstone Networking and Planning Rice University, PO Box 1892, Houston TX, 77251-1892, (713) 527-6059 evan@rice.edu, evan@rice.bitnet, rice!evan, postmaster@rice.edu