IBM 8239 Token-Ring Stackable Hub, Setup And User Manual

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Chapter 6. Concentrator Functions
The functions that are described in this chapter are:
¹
Port Concepts
¹
Address-to-Port Mapping
¹
Port Security
¹
Ring In/Ring Out Concepts
¹
Stack Concepts
¹
Beacon Recovery
Unless otherwise noted, these functions are supported on both models of the 8239.
To configure or obtain status information related to the concentrator functions, use
one of these methods:
¹
A terminal interface command using the EIA-232 interface
¹
A terminal interface command using a Telnet session to an 8239 Model 1 in the
stack
¹
An SNMP request to the appropriate object in the IBM 8239 MIB ( 8239 MIB)
issued to an 8239 Model 1 in the stack
Instructions for accessing information in the remainder of this chapter describe only
access through the terminal interface command.
For a complete listing of commands referenced in this chapter, see the 8239
Command Reference.
Port Concepts
Token-Ring workstations access an 8239 stack ring by being connected to an 8239
port. Each 8239 hub contains 16 RJ-45 ports. Cabling can be either unshielded
twisted pair (UTP) or shielded twisted pair (STP). An optional port expansion card
is available to increase the number of RJ-45 ports in the hub from 16 to 32. The
port expansion card is inserted into a feature slot on the 8239 and is hot-pluggable.
Refer to “16-Port Expansion Feature” on page 3-1 for more information on installing
or removing the port expansion card.
Port Configuration Options
When a Token-Ring station that generates phantom voltage is cabled to the 8239
port,
no default value changes are necessary for that station to insert into the ring.
If the device attached to the 8239 port does not provide phantom voltage, then that
port needs to have 8228_mode enabled in order to insert into the ring. Some
additional configuration options are also described in this section.
Port Administrative Mode
In order for a port to insert into the ring, the administrative mode for that port needs
to be enabled. The default setting for the port administrative mode is enabled. To
disable the port administrative mode, issue the DISABLE PORT terminal interface
command. When the port is enabled, the port’s green status LED is initially off.
When the port is disabled, the port’s green status LED is blinking.

Copyright IBM Corp. 1998
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