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Cisco MGX 8850 (PXM1E/PXM45), Cisco MGX 8950, Cisco MGX 8830, and Cisco MGX 8880 Configuration Guide
Release 5.0.10, OL-3845-01 Rev. B0, August 16, 2004
Chapter 2 Configuring General Switch Features
Configuring Clock Sources
Note
Manual clock distribution provides a revertive function that can apply when the primary clock source
fails and is subsequently restored. A failure is a loss of the primary clock source after the switch has
locked on to that clock source. If the primary clock source recovers and revertive mode is enabled, the
switch automatically reverts to the primary source
The following command example shows how to configure a primary E1 external clock source at the
upper connector of the PXM1E-UI-S3. Note the command punctuation.
mgx8850a.7.PXM.a >
cnfclksrc
primary 7.35 -bits e1
The next example configures a primary network clock source and enables the revertive option.
mgx8850a.7.PXM.a >
cnfclksrc
primary 7.36 -bits e1 -revertive enable
The last example disables the revertive function for an E1 BITS clock.
mgx8850a.7.PXM.a >
cnfclksrc
primary 7.36 -bits e1 -revertive disable
Enabling NCDP on a Node
Use the following procedure to enable NCDP on each node in your network.
Step 1
Enter the cnfncdp [options] command to enable NCDP on the node, set timer values, and specify the
number of nodes in the clocking domain.
M8850_LA.8.PXM.a >
cnfncdp
-distributionMode 1 -maxNetworkDiameter 30 -hello 300 -holdtime
300 -topoChangeTimer 300
describes the options available for the cnfncdp command.
Table 2-7
cnfncdp Command Parameters
Parameter
Description
-distributionMode
The clock distribution mode is either NCDP or manual. If manual,
enter the cnfclksrc and its related commands for synchronization.
Possible entries: 1 for NCDP or 2 for manual clocking
Default = manual (2)
-maxNetworkDiameter
Maximum network diameter measured in hops. This is the maximum
length of the spanning tree, in the range 3 through 200.
Default = 20
-hello
Hello time Interval, in milliseconds, between PDUs. The range is 47
through 60000 milliseconds.
Default = 500 milliseconds
