Specifications

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Software Configuration Guide for Cisco 2600 Series, Cisco 3600 Series, and Cisco 3700 Series Routers
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Chapter 3 Configuring with the Command-Line Interface
Configuring Inverse Multiplexing for ATM Interfaces
Configuring Inverse Multiplexing for ATM Interfaces
To configure an inverse multiplexing for ATM (IMA) interface, you must use configuration mode
(manual configuration). In this mode, you enter Cisco IOS commands at the router prompt.
Note Before you begin, disconnect all WAN cables from the router to keep it from trying to run the
AutoInstall process. The router tries to run AutoInstall whenever you power it on, if there is a WAN
connection on both ends and the router does not have a valid configuration file stored in nonvolatile
random-access memory (NVRAM) (for instance, when you add a new interface). It can take several
minutes for the router to determine that AutoInstall is not connected to a remote Transmission
Control Protocol/Internet Protocol (TCP/IP) host.
This section describes basic configuration, including enabling the interface and specifying IP routing.
Depending on your own requirements and the protocols you plan to route, you might also need to enter
other configuration commands.
Note The T1/E1 physical layer information is configured underneath an interface called interface atm.
The ATM interfaces (representing the individual T1/E1 interfaces) are automatically created
depending on the configuration of the individual T1/E1 interfaces. You cannot directly add or delete
these interfaces.
Each port can be used as an independent T1/E1 ATM port with all the properties and functionality of
ATM interfaces. When the port becomes part of an IMA group, its ATM functionality ceases. At the
same time, the IMA group can use ATM commands.
Note On the 8-port E1 or T1 network module, only four ATM layer interfaces can be operational at the
same time. All the interfaces can be activated (configured as “no shutdown”) but only four at a time
can be operational and pass network traffic.
Configuring the ATM T1/E1 Interface
To configure the ATM interface, follow this procedure:
Command Purpose
Step 1
Router> enable
Password: password
Router#
Enter enable mode. Enter the password.
You have entered enable mode when the prompt
changes to
Router#.
Step 2
Router# configure terminal
Enter configuration commands, one per line.
End with CNTL/Z.
Router(config)#
Enter global configuration mode. You have
entered global configuration mode when the
prompt changes to
Router(config)#.