Specifications

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Cisco MGX 8850 (PXM45) and MGX 8950 Software Configuration Guide
Release 3, Part Number 78-14788-01 Rev. C0, January 2004
Chapter 1 Preparing for Configuration
Planning for Card and Line Redundancy
Note Throughout this guide, the term PXM45 is used to refer to both the PXM45 and PXM45/B cards. The
PXM45 has 128 MB of memory and can scale to 40K connections. The PXM45/B has 256 MB of
memory and will support more than 40K connections in future software releases.
Redundancy setup and configuration is basically the same for AXSM and FRSM cards. AXSM cards or
FRSM-12 cards and their associated lines can be configured for either standalone or redundant
operation. Because a configuration change interrupts service and can require substantial configuration
teardown, it is important to develop a redundancy plan early. The redundancy plan determines how
AXSM and FRSM-12 cards must be installed in the chassis, and how lines must connect to the cards.
Once the hardware is installed, the software configuration team uses the redundancy plan to configure
the switch. The software configuration must match the hardware configuration.
Note Throughout this guide, the term AXSM is used to refer to all the AXSM cards. If a procedure or
paragraph applies to only a specific AXSM card or specific AXSM cards, it will be specified as such.
The first release of the AXSM card is referred to as the AXSM/A card. The second release of AXSM is
referred to as the AXSM/B card.
RPM-PR cards can operate in 1:n redundancy mode, which means that one standby RPM-PR card can
serve as a backup card for multiple active RPM-PR cards.
The Cisco MGX 8850 and the Cisco MGX 8950 switches support the following card and line
redundancy options:
• Standalone AXSM/FRSM-12, redundant lines
• Redundant AXSM/FRSM-12 cards, standalone line
• Redundant AXSM/FRSM-12 cards, redundant lines
• Redundant RPM-PR cards
The following sections provide planning guidelines for these configurations.
Planning Single AXSM/FRSM-12 Front Card Configurations with Redundant
Lines
AXSM/FRSM-12 cards can operate in either standalone or redundant mode. Standalone mode is the
default mode, and standalone cards can be configured for either standalone line operation or Automatic
Protection Switching (APS) line operation, which uses redundant lines for fault tolerance. If a single
AXSM/FRSM-12 front card fails, all calls are lost and the associated lines go out of service. However,
if the AXSM/FRSM-12 is configured to support redundant lines, a failure on the working line causes a
switchover to the protected line, and operation continues.