shoat@cs.glasgow.ac.uk (Mr. David Shoat) (05/22/89)
This group is probably not the best place for this, but while we're on the subject of thin-wire Ethernet: What's the best (only?) way to break out from a DEC DELNI onto thin-wire? The DELNI, for the uninitiated, is a mains-powered device which emulates a piece of coax cable and some transceivers. You just plug up to eight transceiver cables from your systems into the box and it all works. There is also another port on the DELNI into which one is supposed to connect a standard thick- wire transceiver. This should let you break out on to a thick-wire network. Will this work with thin-wire, or do I need a repeater? Does anyone know why my whole damn network crashes every time I throw the switch on the DELNI which enables the external port? Thanks. David Shoat Dept. of Medical Cardiology Glasgow Royal Infirmary.
root@helios.toronto.edu (Operator) (05/26/89)
In article <2987@crete.cs.glasgow.ac.uk> shoat@cs.glasgow.ac.uk (Mr. David Shoat) writes: > >What's the best (only?) way to break out from a DEC DELNI onto thin-wire? Just buy a thinwire transceiver, an in-line type that you insert into the RG58 and which has the standard transceiver cable connector on the other side. Then you plug your DELNI into it with a transceiver cable. >Does anyone know why my whole damn network crashes every time I throw the >switch on the DELNI which enables the external port? > Enabling the external port sends all packets from any of the equipment plugged into the other ports out through it onto the coax connected to it. Since you presumably don't have a coax there (judging by the above question), the packets are going off into never-never land, and as far as the equipment is concerned, the network is dead. If you don't have a coax (or thinwire) connected, there is no reason at all why you would need to enable the external port. This is the point of the switch - you can be isolated or not, as you choose. A DELNI is essentially an ethernet-in-a-box. If *all* your network equipment is in one place, and there's only 8 of them, you don't need to lay any cable. (Actually you can get more than 8 by "cascading" DELNI's - nicely described in the DELNI manual). Remember, for the future, that should your real coax jam or break, you can make your systems on the DELNI stay alive by flipping the switch to disable the external port. We have found this to be extremely useful for our VAXcluster, all the members of which are connected to the same DELNI. -- Ruth Milner UUCP - {uunet,pyramid}!utai!helios.physics!sysruth Systems Manager BITNET - sysruth@utorphys U. of Toronto INTERNET - sysruth@helios.physics.utoronto.ca Physics/Astronomy/CITA Computing Consortium