Link/Seg Traps4-2What is a Link Trap?What is a Link Trap?Some Cabletron Ethernet repeater ports — including RJ45 twisted pair and fiberoptic ports — generate a link signal to monitor the status of their connection withthe device at the other end of the cable segment. If the cable is removed or broken,the port’s link status goes to “No Link” and the repeater generates aportLinkDown trap. When a port in a “No Link” condition receives a link signal,the port goes to a “Link” condition and the repeater generates a portLinkUp trap.Note that devices at both ends of the disconnected or broken cable will generatethe portLinkDown and portLinkUp traps, even when only one end of the cablehas been removed.Enabling and Disabling Link/Seg TrapsAlthough each Cabletron device comes with a number of traps built in to thefirmware, no device will generate these traps unless it is configured to do so. Thiscan be accomplished via Local Management (by enabling traps and entering yourworkstation’s IP address in the Community Names screen), or via the SPMA TrapTable utility, accessible from the icon menu or from the command line. Once trapsas a whole have been enabled, you can use the Link/Seg Traps feature toselectively enable and disable link and segmentation traps as required by yournetwork management needs.To open the Repeater Link/Seg Traps windowfrom the icon:1. Click on the appropriate EMM-E6 icon to display the icon menu.2. Drag down to Link/Seg Traps and release.NOTEUnterminated BNC (thin coax) ports appear in the Hub View as segmented ports. Whenyou attach a thin coax cable or a 50Ω terminator to a port, the repeater generates aportUnsegmenting trap; when you remove the cable or terminator, the repeatergenerates a portSegmenting trap. Note also that devices at both ends of the cable willgenerate the portUnsegmenting and portSegmenting traps, even if only one end of thecable has been disconnected.NOTEBNC (thin coax), AUI, and transceiver ports do not support a link signal. As describedabove, BNC ports respond to changes in link status by generating portSegmenting andportUnsegmenting traps; AUI and transceiver ports do not respond at all to changes inlink status (unless the port has been segmented due to excessive collisions), and willalways display as on, even if no cable is connected.