IBM 8239 Token-Ring Stackable Hub, Руководство по установке и эксплуатации

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MAC-less Devices
A MAC-less device is a Token-Ring station that inserts into the ring but does not
participate in the Neighbor Notification Process.
Note these considerations when MAC-less devices are attached to an 8239 port:
¹
To minimize the network disruption that occurs when identifying which port has
a MAC-less device attached, it is recommended that you attach the MAC-less
device at the last active port on the 8239. For example, if the 8239 has a
16-Port Expansion Feature, attach the MAC-less device to port 32.
¹
To minimize network disruption, you should have at least one active station that
participates in the Neighbor Notification Process attached to the hub to which
an active MAC-less device is attached.
¹
MAC-less devices are represented as having a MAC address of “MAC-less
Device” in the mapping information displayed.
Accessing the Address-to-Port Mapping Information
The mapping information that is gathered is referred to as the
network_map. The
network_map contains the MAC address, and the hub and port associated with that
MAC address. Possible values for the port number are:
¹
A numeric value that represents the port number for a locally attached station
¹
“Management” when the MAC address is for an 8239 Model 1 in the stack
¹
“External” when either of the following conditions exists:
– The MAC address is for a station that is part of the ring segment because it
is attached via an 8239 RI/RO connection (see “Ring In/Ring Out Concepts
(8239 Model 1 only)” on page 6-8).
– The MAC address is connected to a fanout device that is locally attached to
an 8239 port and there are already eight other stations listed for that port
When a MAC address is listed as “External”, no hub number is listed.
“External” stations are included in the network_map only when an 8239 Model 1 is
monitoring the ring with its RMON ring-station group enabled. The default value for
the RMON ring-station group is enabled. Refer to “Configuring RMON” on page 4-7
for more details.
To obtain the address-to-port map information, use the DISPLAY NETWORK_MAP
terminal interface command. This command allows various amounts of mapping
information to be displayed:
¹
DISPLAY NETWORK_MAP ALL_STATIONS (8239 Model 1 command only) to
list all locally attached stations and any external stations
¹
DISPLAY NETWORK_MAP HUB to display only the stations locally attached to
the specified hub. If this hub is an 8239 Model 1, Management Interface is also
included if it is inserted on the ring.
¹
DISPLAY NETWORK_MAP LOCAL_STATIONS to display all stations locally
attached to all the hubs on the stack data ring, including any Management
Interfaces that are present. A maximum of eight stations per port will be
displayed.
6-6
8239 Setup and User’s Guide