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Catalyst 2900 Series XL and Catalyst 3500 Series XL Software Configuration Guide
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Chapter 7 Configuring the Switch Ports
Configuring the LRE Ports
CPE Ethernet Links
The CPE Ethernet link settings define the connection between the CPE Ethernet port and a remote
Ethernet device, such as a PC.
Note
From CMS and the CLI, you can configure and monitor the Ethernet link on a Cisco 575 LRE CPE. You
cannot configure the Ethernet links on a Cisco 585 LRE CPE. You can only monitor the Ethernet links
on the Cisco 585 LRE CPE by using the show remote interfaces status user EXEC command. For
information about the switch LEDs, see
Table 2-8 on page 2-10
and the Catalyst 2900 Series XL
Hardware Installation Guide.
Keep these considerations in mind when you have CPEs connected to the LRE ports:
•
Enable CDP either globally on the LRE switch or on the specific LRE ports.
•
Use the lre shutdown interface configuration command to disable the LRE interface transmitter
on any LRE ports that are not connected to a CPE. This prevents access to the LRE port and prevents
the power emitted from the port from affecting other ports.
•
You cannot configure the flow-control setting on the LRE ports. The flow-control setting on the CPE
Ethernet port is automatically disabled in half-duplex mode and is automatically enabled in
full-duplex mode.
•
You can connect Cisco 575 LRE CPEs and Cisco 585 LRE CPEs to the same LRE switch,.
•
You can hot-swap the CPEs without powering down the switch or disrupting the other switch ports.
Use the show controllers ethernet-controller privileged EXEC command to display the internal switch
statistics, the statistics collected by the LRE switch interface, and the statistics collected by the CPE LRE
interface. For information about this command, refer to the switch command reference.
Considerations for Connected Cisco 575 LRE CPEs
You can configure the Cisco 575 LRE CPE Ethernet port to operate at 10 or 100 Mbps and at half- or
full-duplex mode, depending on the capability of the remote Ethernet device. Autonegotiation for port
speed and duplex mode is supported.
The default speed for the CPE Ethernet port is auto. The default duplex mode is half duplex with back
pressure.
The speeds on the LRE links and CPE Ethernet links do not need to match. However, to prevent the
possible loss of data when the LRE link is slower than the CPE Ethernet link, make sure that the CPE
Ethernet port is set to half-duplex mode. Use duplex autonegotiation only if the remote device supports
802.1X full-duplex flow control. The PC user should notice no significant difference in performance
between 100-Mbps half duplex and 100-Mbps full duplex. Use the duplex and speed interface
configuration commands, respectively, to change the duplex and speed settings on the Cisco 575 LRE
CPE Ethernet port.
