Cisco Systems MGX 8230 Clock Source Types, Clock Source Configuration, Configuration Example

Chapter 6 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 page 2-4for information on the physical connections for external clocking.

•An additional step is necessary to configure an external clock source (see below).

•A UNI interface on a service module or PXM1 UNI port can be a clock source. A line must be active before you can specify it as a clock source.

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 oscillator as the tertiary source. Note that if you specify a tertiary source, it is always the internal oscillator.

Clock Source Configuration

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 service module provides the source, slot is the slot number of the card, and port is the number of the line that provides the clock.

On the PXM1:

•slot is 7 regardless of where the active PXM1 resides.

•port for the inband clock is always 1.

•port for the external clock is always 35.

•port for the UNI line (stand-alone only) depends on the number of lines you have set up on the 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 secondaries.

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

	Cisco MGX 8230 Edge Concentrator Installation and Configuration
6-6	Release 1.1.31, Part Number 78-11215-03 Rev. B0, May 2001