bj@ohsu470.ohsu.edu (Bill Jackson) (03/27/91)
We are building a large multi-vendor network based on Ethernet (10BASET) and fiber backbones. I chose Cayman GatorBoxes for AppleTalk routers and have been generally pleased with them. We are building up the Macintosh side of the network at present and have run across a problem I have not seen before in one particular zone. This zone contains approx 20 Macs of various types, two LaserWriters, two Qume CrystalPrinters and one DataProducts laser printer. The Macs and printers were connected using ad hoc LocalTalk cabling before we integrated them into the Premises Wiring scheme with Farralon PhoneNet connectors and a passive closet star arrangement. The problem we are having is that the non Apple laser printers will "ghost" in and out of the Chooser. They will appear and go away seemingly randomly. The two Qume printers do this constantly; the DataProducts disappears for good when it goes! We have tried all swapping combinations we can think of including putting a LaserWriter on the same leg as the Qume with a PhoneNet link. The LaserWriters remain solid when swapped to the same position as the ghosting printers, and when we connect a LaserWriter back to back with the Qume, they BOTH remain solid! We appear to have no problems with any of the Macs, the AppleShare activities to Sun hosts and telnet sessions seem to work fine, so I must conclude that the wiring is OK. Sure sounds like a termination problem huh? Well why does the fault move WITH the non Apple printers then? The ghosting can been seen in all zones, local and remote, and completely disconnecting the GatorBox isolates it to the local zone. The users naturally say these printers worked fine before we changed the wiring! Anyone seen anything like this - I have no ideas left except to say that I will only support REAL Apple LaserWriters - is this something Apple built in - disruption of "foreign" devices on LocalTalk? :-)