Enterasys Networks 2000 - Manual (Page 150)

Managing Ethernet MicroLAN Switches
5-22 Trap Selection
Information included in a Link State trap will include the board number and port
number associated with the trap.
Segmentation Traps
Ethernet repeaters count collisions at each port. If a port experiences 32
consecutive collisions, or if the port’s collision detector is on for more than
2-3 µs, 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.
Because they do not support the Link signal, unterminated BNC (thin coax) ports
appear as segmented. When you attach a thin coax cable or a terminator to a port,
the repeater generates a portUnsegmenting trap; when you remove the cable or
terminator, the repeater generates a portSegmenting trap. As mentioned 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 the portSegmenting and
portUnsegmenting
traps, even if only one end of the cable has been disconnected.
Information included in a Segmentation trap will include the board number and
port number associated with the trap.
Source Address Traps
The Ethernet MicroLAN Switch can issue several different traps in response to
changes in a port’s Source Address Table:
A newSourceAddress trap is generated when a station port – one receiving
packets from no source addresses, or from one or two source addresses – receives
a 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, and
source address associated with the trap. Trunk ports – those receiving packets
from three or more source addresses – will not issue newSourceAddress traps.
A sourceAddressTimeout trap is issued anytime a source address is aged out of
the Source Address Table due to inactivity. The trap’s interesting information
includes the module and port index, and the source address that timed out.
PortTypeChanged traps are issued when a port’s topology status changes from
station to trunk, or vice versa. The interesting information includes the module
and port index, and the port’s new topology status.
NOTE
Some older repeater devices, and devices with older versions of firmware may include a
slightly different definition of station and trunk status: station ports are defined as those
receiving packets from zero or one source addresses; trunk ports are defined as those
receiving packets from two or more source addresses. If you have any questions about
whether your device or firmware version falls into this older category, or if you would like
information about upgrading your device firmware, contact the Global Technical
Assistance Center.