robelr@bronze.ucs.indiana.edu (Allen Robel) (07/08/90)
1) Many thanks to Bill Westfield for the prompt, official word on the timing issue. 2) We still haven't resolved if this could result in the symptoms described earlier. If, say, the Cabletron repeater was close to being out of spec but in the minus direction (-.01%) and the cisco's interface was out of spec in the plus direction (+.03%), could this potentially cause problems? This would be probably be installation specific e.g. segment length etc. would come into play, right? I must say that the interface that we discovered to be out of spec has caused us *no* problems whatsoever (its connected to a LAN of VAXs that serves our whole campus so gets a lot of traffic). My interest in this has been driven entirely by my curiosity and not out of a need to get anything "fixed." regards, Allen Robel robelr@bronze.ucs.indiana.edu University Computing Services ROBELR@IUJADE.BITNET Network Research & Planning voice: (812)855-7171 Indiana University FAX: (812)855-8299
BILLW@mathom.cisco.com (WilliamChops Westfield) (07/09/90)
We still haven't resolved if this could result in the symptoms described earlier. If, say, the Cabletron repeater was close to being out of spec but in the minus direction (-.01%) and the cisco's interface was out of spec in the plus direction (+.03%), could this potentially cause problems? This would be probably be installation specific e.g. segment length etc. would come into play, right? It is difficult to say, without knowing the exact nature of the problem. I would think that the packets would be much more likely to be dropped at the transceiver or repeater, as the ethernet interface itself is not particurally sensitive to the clock rate. Since in the original problem, other devices on the same MT-800 could see the packets going in both directions, I would suspect something else. I have seen MT-800s that seem to have problems talking between two particular ports, even though everything else seems to work fine. BillW -------
greg%duke.cs.unlv.edu@RELAY.CS.NET (Greg Wohletz) (07/10/90)
> > We still haven't resolved if this could result in the symptoms described > earlier. If, say, the Cabletron repeater was close to being out of > spec but in the minus direction (-.01%) and the cisco's interface > was out of spec in the plus direction (+.03%), could this potentially > cause problems? This would be probably be installation specific e.g. > segment length etc. would come into play, right? >It is difficult to say, without knowing the exact nature of the problem. >I would think that the packets would be much more likely to be dropped at >the transceiver or repeater, as the ethernet interface itself is not >particurally sensitive to the clock rate. Since in the original problem, >other devices on the same MT-800 could see the packets going in both >directions, I would suspect something else. I have seen MT-800s that >seem to have problems talking between two particular ports, even though >everything else seems to work fine. well, I'm the guy who posted the original message. Guess when the gateway in question was purchased. Guess what is printed on the crystals. Yep, you guessed right. I've been debuging this problem for about a month now, so I have a little more info: The packets sent by the cisco are recieved by all machines on both sides of the repeater just fine, the problem is that the gateway ignores packets that are sent to it across the repeater. A check of our MCI cards revealed that they do indead have the fs200 crystals (all 6 ethernets). So, does this make sence? As far as the cisco is concerned the packets generated by the repeater are too slow, so it drops them? I guess I'll be giving cisco a call tomorow to find out what my options are. My experiances with them up to this point have been good, but I'm pretty annoyed that I wasted a month on this problem (some of our machines are still not up). Unfortunatly my warantee period was over about 1 month before it caused us any problems. I wish I had at least gotten a letter telling me what to watch out for since it was apparently a known problem. Anyway thanks to this list I may still regain my sanity :-) --Greg