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

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The port’s green LED is blinking; the yellow LED is off. The port status will be:
– PHANTOM when phantom voltage is present
– NO PHANTOM when phantom voltage is not detected
For more information about the port status LEDs, refer to “Port Status” on
page 5-3.
Address-to-Port Mapping
To aid network administrators in managing their networks, the 8239 provides
information that identifies which MAC addresses are connected to which ports on
the 8239. This capability is called
address-to-port mapping and is also referred to
as mapping. No configuration options are needed for the 8239 to perform mapping;
it is done automatically and the mapping information is available on request.
Stations that are directly attached to one of the 16 or 32 ports on an 8239,
including fanout devices and MAC-less devices, are referred to as
local stations.
Stations attached to external devices can also be identified when an 8239 Model 1
is used; these stations are referred to as
external stations.
Mapping identifies what MAC addresses or set of MAC addresses (if a fanout
device is used) are assigned to a port. Mapping also determines if a MAC-less
station is attached to an 8239 port.
Fanout Devices
A fanout device is a device to which multiple stations can be attached; the device
itself is then attached to a single port on the 8239. The IBM 8226 and the IBM
8228 are examples of fanout devices.
Note the following considerations for the attachment of fanout devices to an 8239
port:
¹
If a fanout device has more than 8 stations attached to it, only the first 8
stations are identified with a hub and port assignment; all other stations on the
fanout device are identified as "External" if information is being displayed using
an 8239 Model 1 that has RMON ring station statistics group enabled.
¹
If no active stations are attached to the fanout device, the fanout device is
recognized as a MAC-less device.
¹
A MAC-less device that is attached to the fanout device, as opposed to being
attached to the 8239 port, will not be included in the mapping information.
¹
The ability to display fanout devices does not depend on whether or not
8228_mode is enabled for a port (refer to “Port Concepts” on page 6-1).
¹
If multiple fanout devices are attached to consecutive active ports and the last
station on the first fanout device is moved to the first station on the next fanout
device, the mapping facility will not be able to detect the change.
¹
If multiple fanout devices are attached to the same 8239, it is recommended
that you have at least one active single station inserted between the fanout
devices.
Chapter 6. Concentrator Functions
6-5