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Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide
OL-10101-02
Chapter 12 Configuring LRE
Configuring LRE Ports
To remove a sequence from a port, use the no sequence sequence-name interface configuration
command.
To display the LRE link statistics and sequence information on the LRE ports, use the show controllers
lre status sequence details privileged EXEC command.
Using Rate Selection to Automatically Assign Profiles
An LRE network requires a profile to be configured for each LRE port that is connected to a CPE device.
The default is LRE-10 on the Catalyst 2950ST-8 LRE and 2950ST-24 LRE switches and LRE-6 on the
Catalyst 2950ST-24 LRE 997 switch. You can use the rate selection feature to automatically choose a
profile from a set of profiles that the switch port uses to establish an LRE link (a link between an LRE
switch port and an attached CPE device).
Rate selection is enabled by default, but you must choose a sequence for rate selection to start (in other
words, there is no default sequence defined). When rate selection is running, the switch chooses the
profile for the LRE interface from a sequence, or predefined series of profiles, that are configured for
that interface. The rate-selection algorithm begins with the first profile in the sequence and successively
tries the next profiles (in descending order) until a link is established with the CPE device.
When rate selection is enabled, the LRE switch executes rate selection in these scenarios:
• When the switch is started up
• When you enable the rate selection feature
• When you connect a new CPE device to the switch
• When a link is lost for 25 seconds before being restored
• When a configured sequence is modified
In any of these cases, rate selection obtains the optimal profile for your line conditions.
Note When an LRE link is lost for fewer than 25 seconds, the switch does not execute rate selection to
re-establish the link. The link is re-established at the profile used before link loss.
The switch chooses the appropriate profile for an LRE interface when it executes rate selection. If line
conditions of the LRE interface change, rate selection must be executed again.
Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 interface interface-id Enter the number of the LRE port to be configured, and enter interface
configuration mode.
Step 3 sequence sequence-name Enter the port sequence name (select from the list in Table 12-3 on
page 12-5 or Table 12-4 on page 12-5).
Step 4 end Return to privileged EXEC mode.
Step 5 show controllers lre status sequence Verify the change.
Step 6 copy running-config startup-config (Optional) Save your entries in the configuration file.