dan@lclark.UUCP (Dan Revel) (07/31/90)
We have a couple Appletalk/Localtalk networks on campus with about 25 macs (pluses and SEs) and 5 imagewriter IIs. We have recently connected these nets with other localtalk nets using Shiva NetBridges. Now the Imagewriters (w/appletalk option cards) have taking to jamming our networks. I am told that this behavior may be related to printing packets getting lost and printers not recovering from the error. Does anyone know if this is indeed what is happening? Any suggestions on how to go about alleviating the problem? ( We have discussed a number of possibilities that all involve throwing money at the problem, e.g. replacing the imagewriters with or reconfiguring each net with a starcontroller ) Comments? Thanks, Daneher -- dan@lclark tektronix!reed!lclark!dan Dylsexics untie! (-|
randy@ux1.cso.uiuc.edu (Randy E. Cotton) (08/07/90)
dan@lclark.UUCP (Dan Revel) writes: >We have a couple Appletalk/Localtalk networks on campus with >about 25 macs (pluses and SEs) and 5 imagewriter IIs. We have >recently connected these nets with other localtalk nets using >Shiva NetBridges. Now the Imagewriters (w/appletalk option >cards) have taking to jamming our networks. Me too! Me too! I have one particular Imagewriter II that periodically jams some or all Appletalk communications. When it happens the red LED light flashes a particular sequence - something like two short flashes and a long flash, not sure. This is especially catastrophic for us because we run the Novell Mac VAPs and when the Imagewriter freaks out, the connections to the file server evaporate. I had to quarantine the offending printer. Does anyone have any idea what could be causing this? I suspect it's something wrong with the appletalk option board, but I would be much more comfortable knowing more precisely what the problem was before I go replacing these boards willy nilly. > I am told that >this behavior may be related to printing packets getting lost >and printers not recovering from the error. Does anyone know >if this is indeed what is happening? Any suggestions on how >to go about alleviating the problem? ( We have discussed a >number of possibilities that all involve throwing money at the >problem, e.g. replacing the imagewriters with or reconfiguring >each net with a starcontroller ) Comments? >Thanks, >Daneher >-- >dan@lclark >tektronix!reed!lclark!dan Dylsexics untie! (-| -- ____________ "... the fact is that most people don't find the words CONFIG.SYS romantic and are unashamed of that fact" - Boris Levitin
wcc@cup.portal.com (wcc - usa) (08/08/90)
dan@lclark.UUCP (Dan Revel) writes: > >We recently connected these nets with other localtalk nets using > >Shiva NetBridges. Now the Imagewriters (w/appletalk option > >cards) have taking to jamming our networks. > > Me too! Me too! I have one particular Imagewriter II that periodically > jams some or all Appletalk communications. > This is especially catastrophic for us > because we run the Novell Mac VAPs and when the Imagewriter freaks out, > the connections to the file server evaporate. I had to quarantine the > offending printer. You too? ImageCritters do that. You are suffering a "mystery" ImageCritter Crunch. Let me tell you about one we tracked down. Our gateways were sending a perfectly legal broadcast packet that included some routing information. The packets were absoutely legit, and should have been filtered out (on the basis of protocol type and socket number) by all other devices. Not the ImageCritters. They seemed to like the packet so much that they either swooned away (dead until power-cycle), or they'd jam the network, usually with CTS packets or something. Power-cycle fix again. > Does anyone have any idea what could be causing > this? I suspect it's something wrong with the appletalk option board, > but I would be much more comfortable knowing more precisely what the > problem was before I go replacing these boards willy nilly. Adding one null tuple to the END of the packet changed it enough so the ImageCritters ignored it!!! This looks like they are looking at the LENGTH field of incoming packets rather than the socket or type fields somewhere in the incoming filter code. It's likely they are objecting to something the NetBridges are putting out. It is also highly likely to be topology and configuration dependent, as packets change (length and content) on different parts of the network. So they will fail in some places and not in others. Maybe you can find a "magic backwater" somewhere to put all of them :-). Apple released a new version of the ROMS for the AppleTalk card months ago. It would be worth getting one of these and seeing if it fixes your problems. > >Any suggestions on how > >to go about alleviating the problem? ( We have discussed a > >number of possibilities that all involve throwing money at the > >problem, e.g. replacing the imagewriters with or reconfiguring > >each net with a starcontroller ) Comments? Try replacing the ROMS first. The new version may fix the problem. If you do and it does then please tell us all here on the net. The StarController wouldn't help at all. The InageCritters would still see all the packets (including the ones they choke on) and the StarController would still faithfully retransmit the net-jamming packets. No solution. Tom Evans wcc@cup.portal.com till 18th. Aug. tom@wcc.oz.au from 18th. Sep. Webster Computer Corporation 2109 O'Toole Ave, Suite J San Jose CA 95131-1303 Ph (408) 954-8054, FAX (408) 954-1832