Lab A.9: Serial Interface Commands
583
You can verify that both addresses are configured on the interface
with the show running-config command (sh run for short).
Router#sh run
Building configuration...
Current configuration:
[output cut]
!
interface Ethernet0
ip address 172.16.20.2 255.255.255.0 secondary
ip address 172.16.10.2 255.255.255.0
!
Lab A.9: Serial Interface Commands
T
o configure a serial interface, a couple of specifics need to be dis-
cussed. Typically, the interface will be attached to a CSU/DSU type of device
that provides clocking for the line. However, if you have a back-to-back
configuration--for example, in a lab environment--one end must provide
clocking. This would be the data communication equipment (DCE) end of
the cable. Cisco routers, by default, are all data terminal equipment (DTE)
devices, and you must tell an interface to provide clocking if it is to act as a
DCE device.
1.
You configure a DCE serial interface with the clock rate command.
Router#config t
Enter configuration commands, one per line. End with
CNTL/Z.
Router(config)#int s0
Router(config-if)#clock rate ?
Speed (bits per second)
1200
2400
4800
9600
19200
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