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Cisco 10008 Router PRE4 Installation and Configuration Guide
OL-13840-01
Configuring Network Timing
Configuring Network Timing
Network Timing allows you to configure a common clock source, to drive the transmit clock on all the
serial interfaces in the Cisco 10000 series router on the line cards that support this feature. Apart from
the PRE4, the Cisco 10000 series router also supports the Network Timing module implemented as a
daughter card on the PRE4.
This section describes items that need to be configured to enable Network Timing on the Cisco 10000
series router.
•
•
Verifying the Network Timing Configuration, page 22
•
Configuration Examples, page 23
Configuration Tasks
This section explains the steps to configure Network Timing on the Cisco 10000 series router.
•
Enabling Network Timing, page 21
•
Selecting Clock Sources, page 21
•
Selecting Participating Subslots, page 22
•
Reverting to a Higher Priority Clock, page 22
Enabling Network Timing
Though several items must be configured to enable the Network Timing feature in the Cisco 10000 series
router, the
network-clock
command is the main parser command issued from the global configuration
mode. The other options included are specified below:
Router(config)#
network-clock ?
Selecting Clock Sources
Select a reference clock from the existing clock sources, to be used as the central timing source. When
choosing a source clock, also select its priority.
The
network-clock select
command is issued from the global configuration mode, to select a clock
source.
Router(config)#
network-clock select ?
Command
Purpose
Router(config)#
network-clock select
Selects a network clock source. See
Router(config)#
network-clock participate
Enables or disables a slot/subslot from
participating in network-clocking. See
Participating Subslots, page 22
.
Router(config)#
network-clock revertive
Reverts the reference clock to the highest priority
after the clock recovers from a previous failure.
See