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Cisco BPX 8600 Series Installation and Configuration
Release 9.3.30, Part Number 78-12907-01 Rev. E0, May 2005
Chapter 25 Configuring SONET Automatic Protection System
APS 1+1 (Card and Line Redundancy)
The switching of the front cards is controlled by switch software under the Y-redundancy protocol. The
switch software performs switching between the two cards in the event of a front card failure, front card
downed, front card failing self-test, and so on.
You may add APS at any time after Y-redundancy is configured as long as the protection line is in the
standby state. You may add APS even if lines and trunks are upped and the card is passing traffic.
Note
Normally when APS and card redundancy are implemented together, the term YRED really means
card redundancy, as in this case there is no Y-cabling involved. An exception exists when the BXM
is attached to a MGX 8220 (feeder shelf) or other device which does not support APS. In that case,
Y-cables or straight cables may be used with APS.
When APS is configured on a card pair, switch software checks to ensure that both cards match and
support APS.
For APS 1+1 redundancy, the same numbered ports on adjacent BXM back cards are used. The
maximum number of connections supported does not change, as the complete connection capability of
the cards is available.
Note
Using only one front card and two back cards is not a valid configuration when adding APS
capability, and the APS alarm capability is reduced when the standby card is not available.
Application Notes for APS 1+1
This section describes the notes for APS 1+1.
Using switchcdred/switchyred command
Note
Entering
switchcdred
or
switchyred
execute the same command. The newer name is
switchcdred
which replaces
switchyred
, but
switchyred
may still be used for those familiar with that command.
The
switchcdred (switchyred)
command can be used to switch between an active and standby front card
in an APS 1+1 configuration. For example, you might want to do this to test the standby front card.
Following a
switchcdred (switchyred)
, or active card reset, the BXM card is sent a message from switch
software to have it perform an APS switch to align itself with the last user
switchapsln
switch request.
If the last user request is “clear”, full automatic APS switching is in effect with the working line in the
active state by default. When there is no last user switch request to switch any particular line,
for
example, protection line, the working line becomes active.
Содержание BPX 8650
Страница 49: ...P A R T 1 The BPX Switch ...
Страница 50: ......
Страница 159: ...P A R T 2 Installation ...
Страница 160: ......
Страница 273: ...P A R T 3 Initial Configuration and Network Management ...
Страница 274: ......
Страница 311: ...P A R T 4 Configuring Connections ...
Страница 312: ......
Страница 487: ...P A R T 5 Troubleshooting and Maintenance ...
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Страница 533: ...P A R T 6 BPX Specifications ...
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Страница 555: ...P A R T 7 Appendices ...
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