Cisco SR2016T-NA Reference Manual page 417

Chapter 2 Cisco CMTS Configuration Commands
frequency
To create a DOCSIS configuration file that specifies the center frequency for downstream channel for a
CM, use the frequency command in cable config-file configuration mode. To remove the downstream
channel frequency, use the no form of this command.
Syntax Description freq
Defaults The CM defaults to scanning the downstream for available downstream frequencies.
Command Modes
Cable config-file configuration
Command History Release
12.1(2)EC1
12.2(4)BC1
Usage Guidelines This command typically is not used because the CM during its registration process scans the downstream
frequency spectrum for an available downstream channel. If the CM finds a channel and can successfully
lock on it, the CM uses that channel until the CMTS instructs otherwise.
However, there could be situations in which you want to specify that a CM should use a specific
downstream center frequency. In these situations, use the frequency command to require the CM to use
that frequency. For example, specifying a particular center frequency can improve the ability of the
network to recover when a CM loses downstream lock, because it retries only the one frequency instead
of scanning the entire downstream spectrum.
Note The frequency specified by the configuration file must match the output frequency of the upconverter;
otherwise, the CM cycles offline each time the configuration file is received.
Examples
The following example shows how to specify the downstream center frequency for a DOCSIS
configuration file:
router(config)# cable config-file fixedfreq.cm
router(config-file)# frequency 453000000
router(config)# exit
OL-1581-08
frequency freq
no frequency freq
Specifies the downstream frequency in multiples of 62500 Hz. Valid range
is 88 to 860 MHz.
Modification
This command was introduced.
Support was added to the Release 12.2 BC train.
Cisco Broadband Cable Command Reference Guide
frequency
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