Cisco 2950G 24 Software Configuration Guide - Page 256

Configuring LRE Ports Chapter 10 Configuring LRE Note When the default speed is set to 10 or 100 Mbps with half duplex, the values set are the same. If the remote values are 10 Mbps with full duplex, the Cisco 575 LRE CPE Ethernet port is profile independent. All LRE profiles are set to be 10 Mbps with half duplex except for LRE-10 (the default), which is set to 10 Mpbs with full duplex. For a setting of 100 Mbps with full duplex, the value is set to 100 Mbps with half duplex. 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 cpe duplex and cpe speed interface configuration commands, respectively, to change the duplex and speed settings on the Cisco 575 LRE CPE Ethernet port. Considerations for Connected Cisco 585 LRE CPEs You can configure the Cisco 585 LRE CPE Ethernet port speed and duplexing from the command line, depending on the capability of the remote Ethernet device. Autonegotiation for CPE port speed and duplex mode is supported. The default speed for the CPE Ethernet ports is auto. The default duplex mode is half duplex at 100 Mbps with back pressure. You can enable or disable the CPE Ethernet ports on a per-port basis. The loopback interface configuration command is not supported on the LRE ports. External loopback on the LRE ports is also not supported. Connecting a CPE Ethernet port to another Ethernet port on the same CPE device can create a loop. If this happens, the switch stops sending to the CPE device and blocks Ethernet traffic coming from the CPE device. Assigning a Global Profile to All LRE Ports Global profiles are set on a switch-wide basis. Port sequences, global sequences, and port profiles have priority over global profiles (see the "Precedence" section on page 10-11 for a full discussion of rate selection precedence). If you assign a global profile to the switch, it cannot over-ride any previously or subsequently set sequence port profile. (For further information on sequence and profile precendence, see Guidelines for Using LRE Profiles, page 10-7.) Changes to the global profile settings are immediately put in effect, and the global mode automatically becomes the active mode. Beginning in privileged EXEC mode, follow these steps to assign a global profile to the LRE ports: Step 1 Step 2 Step 3 Step 4 Command configure terminal lre profile profile_name end show controllers lre profile details Purpose Enter global configuration mode. Enter the global profile name. Select from the list in Table 10-1. Return to privileged EXEC mode. Verify the change. 10-8 Catalyst 2950 Desktop Switch Software Configuration Guide 78-14982-01