Cabletron Systems SEHI-22/24, SEHI-32/34 Link/Seg Traps, What is a Segmentation Trap?, Chapter

Chapter 3

Link/Seg Traps

What are Link and Segmentation traps; enabling and disabling these traps at the device, module, and port levels

Among the traps which Cabletron devices are designed to generate are traps which indicate when a repeater port gains or loses a link signal, when the repeater segments (disconnects) a port due to collision activity, and when a segmented port becomes active again. In some networks, these Link and Segmentation traps may be more information than a network manager wants to see. So SPMA provides you with a means to selectively enable and disable Link and Segmentation traps: you can turn traps on and off for all ports on the SEHI, all ports on a selected module or modules, or for individual ports.

NOTE

SPMA does not accept the trap messages; that task is left to your network management system. (See the appropriate network management system documentation for details about viewing trap messages.) When this utility is used in stand-alone mode, traps will either be ignored when they return to the workstation from which you are running SPMA for the SEHI, or they will turn up at another management workstation which has been configured to accept traps. Note also that, regardless of the configuration performed using this utility, NO traps will be sent by the device unless its trap table has been properly configured; see the SEHI hardware manual and/or the Trap Table chapter in the SPMA Tools Guide for more information.

What is a Segmentation Trap?

Cabletron’s Ethernet repeaters count collisions at each port. If a port experiences 32 consecutive collisions, the repeater segments the port to isolate the source of the collisions from the rest of the network. When the repeater segments a port, it generates a portSegmenting trap. As soon as a segmented port receives a good packet, the repeater reconnects the port to the network and generates a portUnsegmenting trap.

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