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Cisco MGX 8230 Edge Concentrator Installation and Configuration
Release 1.1.31, Part Number 78-11215-03 Rev. B0, May 2001
Chapter6 Card and Service Configuration
The Processor Switching Module
•For external Stratum 3 clock sources, the PXM-UI-S3 back card must be used.
Note See the “Making External Clock Connections” section on page2-4 for information on the
physical connections for exte rnal cl oc ki ng .
•An additional step is necessar y to co n figur e an ex te rnal clock source (see below).
•A UNI interface on a service module or PXM 1 UNI port can be a clock source. A line mu st be active
before you can specify it as a cloc k s o u rc e.
Clock Source Types
The clock types are primary, secondary, and tertiary.
For example, you could configure an external clock source as the primary source, a line as a secondary
source, and the internal oscill at or a s th e t er ti ar y sou r ce. N ot e t ha t i f yo u sp eci fy a te rtiary source, it is
always the internal oscillator.
Clock Source Configuratio n
After the PXM1 broadband interfaces and the service module lines have been configured, you can
configure the clock sources through the CiscoView application or the CLI. If you use the CLI, execute
cnfclksrc on the active PXM1 one time for each clock source:
cnfclksrc <slot.port> <clktyp>
The parameter slot.port specifies the clock source. If a se rvi ce module provides the source, slot is the
slot number of the card, and port is the n umb er o f th e lin e that provides the clock.
On the PXM1:
•slot is 7 regardless of where the active PX M 1 re s ide s.
•port for the inband c lock is always 1.
•port for the external clock is always 35.
•port for the UNI line (stand-alone only) depends on the number of li nes you have set up on th e back
card.
The value for clktyp is P for primary, S for secondary, T for tertiary, or N for null. The only purpose of
null is to remove the clock configuration that currently applies to the specified source (slot.port).
Caution Be careful not to set multiple primaries and seco nda ries .
Configuration Example
For example, to configure the inband interface as the primary clock source and an external clock device
as the secondary source, execute the following two commands.
Step 1 Specify the clock source:
a. For an external clock source:
popeye1r.1.8.PXM.a > cnfclksrc 7.35 S