Specifications

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Cisco MGX 8800/8900 Series Software Configuration Guide
Release 5.1, Part Number OL-6482-01, Rev. A0, January 25, 2005
Chapter 9 Switch Operating Procedures
Managing Manually Configured Clocks Sources
Delete Manual Clock Sources
Deleting a clock source deletes the definition of the clock source, not the clock source itself. You might
want to delete a primary or secondary clock source definition so that you can reassign the clock source
to another line.
To delete a clock source, use the following procedure.
Step 1 Establish a configuration session using a user name with SUPER_GP privileges or higher.
Step 2 Display the clock source information by entering the dspclksrcs command.
You will need the information in this display to delete the clock source.
Step 3 To delete a clock source, enter the delclksrc command.
mgx8830a.1.PXM.a > delclksrc <priority>
The following example deletes a primary clock source:
mgx8830a.1.PXM.a > delclksrc primary
Step 4 To verify that a clock source has been deleted, enter the dspclksrcs command. When the primary or
secondary clock source is deleted, the clock type is set to null.
Restore a Manual Clock Source After Failure
The revertive option for clock sources connected to the PXM allows a primary clock source to resume
operation as the primary clock source after a failure and restoration of the clock signal. However, if you
have the revertive option disabled, you will have to manually reconfigure a failed primary clock source
after it recovers before it can resume operation as the primary clock source.
To reconfigure a BITS clock source, see the “Manually Configuring BITS Clock Sources” section in
Chapter 2, “Configuring General Switch Features.” To reconfigure a PXM1E line clock source, see the
“Configuring PXM1E Line Clock Sources” section in Chapter 3, “Provisioning PXM1E Communication
Links.” To reconfigure an AXSM line clock source, refer to the Cisco ATM Services (AXSM)
Configuration Guide and Command Reference for MGX Switches, Release 5.
Tip Enter the dspclksrcs command to display the current configuration settings for the primary clock source.
Having this information available makes it easier to re-enter the cnfclksrc command.
Note To change a clock source on the PXM from nonrevertive to revertive, enter the cnfclksrc with the option
–revertive enable.
When the primary clock source is restored on the master clock node, you may have to reconfigure the
primary clock source at each remote node where the node has switched from the primary source to the
secondary source. This reconfiguration is necessary only if the local node has detected a change in the
master clock source.
To determine if you need to reconfigure the primary clock at a nonmaster node, enter the dspclksrcs
command. If the active clock has changed to either secondary or internal clock, you must use the
cnfclksrc command to reconfigure the primary clock source for that node.