CHAPTER
4-1
Cisco MGX 8800/8900 Series Hardware Installation Guide
Releases 2 - 5.2, Part Number OL-4545-01, Rev. H0, May 2006
4
Planning for Card Redundancy, Line Redundancy, and Bulk Distribution
This chapter describes how to plan for card redundancy, line redundancy, and bulk distribution on MGX
switches. The card redundancy feature uses a secondary card of the same or similar type (MPSM-8-T1E1
cards support other card types) to serve as a standby card and to take over if the active card fails. The
line redundancy feature extends this same type of fault tolerance to individual lines connected to the
switch. (In this chapter, switch refers to the MGX switches and the MGX 8880 gateway.)
Bulk distribution is a feature that uses an SRM card to aggregate T1 or E1 traffic from selected service
modules and transmit that traffic over higher speed back cards connected to the SRM. Aggregated traffic
received at the SRM cards is distributed to the individual service modules. The primary featu re of bulk
distribution is that it enables a switch to use fewer T3 or OC-3 lines instead of many T1 or E1 lines. A
secondary benefit is that SRME cards can provide line redundancy to cards that otherwise could not use
that feature.
Because a configuration change for any of these services has the potential to interrupt service and can
require substantial configuration teardown, it is important to develop a plan for these services early. This
plan determines how controller cards and service modules must be installed in the chassis, and how lines
must connect to the cards before configuration starts. Once the hardware is installed, the software
configuration team uses this plan to configure the switch. For the switch to operate properly, the
hardware installation must match the planned software configuration.
The features described in this chapter are not supported on all cards. Ta ble 4-1 lists all the card types and
the features they support.
Table4-1 Card Redundancy, Line Redundancy, and Bulk Distribution Features
per Card
Card Type
Card Redundancy
Options Line Redundancy Supported Bulk Distribution Supported
AUSM8T1/B1
AUSM8E1/B1
Standalone None2Yes
1:N
AXSM-1-2488
AXSM-1-2488/B
AXSM-1-9953-XG
Standalone None No
1:1 Intercard APS
AXSM-2-622-E Standalone None No
1:1 Intercard and intracard APS