TR Follies Hi Louis ! >Peter, this is an intellectual challenge. That's why I am at a disadvantage. DS address witheld sent in this month's whatthehell challenge. Nah. That's Token Ring for Beginners. 1st Rule you learn: Station ports are for stations only, Ring In / Ring
Out
>They had me use the setup aid in the bad port
with the network live at
Aha. The self-acclaimed "experts" weren't any better. It's some sort
of a miracle that the entire net didn't go down. Usually "breaking the
ring" with a setup tool causes the other ports to shut down and drop the
relays.
>I pulled the plug labeled receiving in the LAN closet and inserted the setup aid. Once the setup aid finished (red light blinked) the 2 lanmanager servers that run the POS system (plugged in on the POS closet) started beeping and reporting beaconing. Awww. Great. You *may* try to disconnect a station for about one - two
>I was told that the 2 closets were on separate
loops by the staff at work
Sigh. What more to say ? It's the usual stuff. Everywhere - all the time. >Is it possible to connect loops through one of the 1-8 ports on a 8228, or would it have to run through either the RI/RO ports? No. You cannot. Not that easy. There were "station splitters" available from e.g. Olicom that allowed to abuse a "station port" for another "stub 8228", which holds "another subset" of stations. Basically and directly you cannot a) connect 2 station ports of
two
For a) you need to RI/RO daisy-chain them. Usually no problem - even
in
>Do you think that the troubleshooting I went
through the first time could
Ugh ... not true normally. You *sure* hear the relays click on / off
when a
>Lastly to note is that once I had unplugged all
the nodes from the LAN
That's the consequent method to get it done. Usually all alone in the
>I didn't test the dead port that I had found the first time though, it makes me wonder if I happened to fix that as well this time around. Well - "Why not ?" You do them all - or none. If there is one really defective port there you have the potential danger of running into the same scenario once again later. There are *rare* incidents where an 8228 is really defective - but I *had* that. And you can only find out with testing *all* ports ... best with the RI/RO cables detached too and a second Tester in the RI or RO port. When the lamp on the station port stays out the RI (or RO) port *must* come on. That's the indication that the 8228-internal data path is working. You can rely however on the "click-...-clack" noise fo the station relay only and hope everything internally is well-fabricated. Most are - working fine for decades. Some are not. We had a number of Brazil-made 8228s, which had an internal fault and did not pass the signal to either RI or RO (or both on one). All station ports clicked fine .... Causes For Permanent "relay static" in a group of MAUs 1. Worn out plugs, improperly seated, partially seated
and lacking the
So that's *my* experience of over 13 years with 8228 units ... :-)
What Are the Differences between Bridges, Routers, and Gateways? A bridge is a device that interconnects two subnets using the MAC address of stations. Bridges operate at layer 2 of the OSI protocol stack. Because MAC addresses are protocol independent, a bridge is very useful for physical network extension, speed matching, and wiring optimization. However, since a bridge is essentially transparent to the attaching stations, dependencies upon such protocol variables as timers, flow control and error recovery are not supported. Thus, problems may arise if too many workstations are bridged. These include issues such as broadcast storms, time-outs and congestion-caused delays in response times. A router is a device that interconnects two or more network segments on the basis of OSI layer 3 addresses. Because such addresses have protocol dependencies, a router must either participate in the protocols for purposes of routing, flow control, and error recovery, or must encapsulate protocol dependent information in frames supported by the routers. Even with encapsulation however, a router must understand the network topology and where to send data frames. Routers maintain topology information as a result of an exchange of topology information with other routers in the network. Communication of topology information between the routers may use open standards for exchange such as OSPF or EGP or vendor-specific protocols. They do not assume responsibility for the integrity of the address information used within the network. A gateway is a device that handles interconnection and transfer of information between entities in layers 4 through 7 of the OSI Reference Model. Thus a gateway is required when an entity using one protocol needs to communicate with an entity using another protocol (protocol conversion), when the addressing structure of two entities is inconsistent, or when connection is required between independent networks. |