Cabletron Systems 2000 User Manual

Also see for 2000: User guide Getting started guide

Contents

Trap Selection5-23Managing Ethernet MicroLAN Switchesthe 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.Devices at both ends of the disconnected or broken cable will generate theportLinkDown and portLinkUp traps, even when only one end of the cable hasbeen removed.Note that BNC (thin coax), AUI, and transceiver ports do not support a linksignal. BNC ports respond to changes in link status by generatingportSegmenting and portUnsegmenting traps (see description, below); AUI andtransceiver ports do not respond at all to changes in link status (unless the porthas been segmented due to excessive collisions), and will always display as on,even if no cable is connected.Information included in a Link State trap will include the board number and portnumber associated with the trap.Segmentation TrapsCabletron’s Ethernet repeaters count collisions at each port. If a port experiences32 consecutive collisions, or if the port’s collision detector is on for more than2-3 μs, the repeater segments the port to isolate the source of the collisions fromthe rest of the network. When the repeater segments a port, it generates aportSegmenting trap. As soon as a segmented port receives a good packet, therepeater reconnects the port to the network and generates a portUnsegmentingtrap.Note that, because they do not support the Link signal, unterminated BNC (thincoax) ports appear as segmented. When you attach a thin coax cable or aterminator to a port, the repeater generates a portUnsegmenting trap; when youremove the cable or terminator, the repeater generates a portSegmenting trap. Asmentioned above, these traps can serve as notification of changes in link status.Note, too, that devices at both ends of the cable segment will generate theportSegmenting and portUnsegmenting traps, even if only one end of the cablehas been disconnected.Information included in a Segmentation trap will include the board number andport number associated with the trap.Source Address TrapsThe Ethernet MicroLAN Switch can issue several different traps in response tochanges in a port’s Source Address Table:A newSourceAddress trap is generated when a station port – one receivingpackets from no source addresses, or from one or two source addresses – receivesa packet from a source address that is not currently in its source address table.Information included in this trap includes the module number, port number, andsource address associated with the trap. Trunk ports – those receiving packetsfrom three or more source addresses – will not issue newSourceAddress traps.