Specifications

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Cisco IGX 8400 Series Provisioning Guide, Release 9.3.3 and Later Releases
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Chapter 2 Cisco IGX 8400 Series Cards
Nodal Processor Module
Each operating IGX node must have an SCM. Removal of the SCM disrupts system operation. The SCM
resides in back card slot 1 (for information on installing back cards, see the Installing the IGX chapter
in the Cisco IGX 8400 Series Installation Guide).
Tip One SCM is sufficient to support redundant NPM front cards.
External Clock Sources
The external clock connector is a 15-pin input designed to allow network synchronization signals from
an EIA/TIA-422 external clock source. The external clock signal must be 1.544 MHz or 2.048 MHz.
The external clock source can be configured as a primary, secondary, or tertiary clock source.
Trunk or line inputs can also serve as a source for timing for the node. If no clock source is detected, the
node will use the internal IGX clock (on the SCM) as the clock source for the node.
An external clock source can be connected to the SCM card using the external clock adapter cable. The
external clock device can be either 1.544 MHz or 2.048 MHz EIA/TIA-422 square wave signals.
Selection is made through software.
For information on configuring external clock sources for an IGX node, see the “Making External Clock
Connections” section on page 3-47 in the Cisco IGX 8400 Series Installation Guide.
NPM Installation
The active and redundant NPMs must be installed in slots 1 and 2. The NPM front card and SCM back
card use a standard IGX card installation (see the “Inserting the Cards” section on page 3-8 in the
Cisco IGX 8400 Series Installation Guide).
NPM Management
Primary management tasks include maintaining and upgrading the switch software and firmware images
for the IGX node, monitoring alarm states, and collecting statistics. In addition, Cisco recommends
exercising redundant NPMs occasionally using the switch software command, switchcc.
Switch Software Management
Switch software management tasks can be conducted through a network management station running a
network management program, such as Cisco WAN Manager, or through using the switch software
command-line interface (CLI).
Replacing or Upgrading the Switch Software
Before upgrading the switch software on a node, confirm the compatibility of the switch software and
the firmware image(s) found on the cards installed in the node. Some switch software upgrades may
require an additional firmware upgrade on some or all of the cards installed in the node.
For information on switch software and firmware compatibility, see the Compatibility Matrix at
http://www.cisco.com/kobayashi/sw-center/sw-wan.shtml.