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Catalyst 2950 Desktop Switch Software Configuration Guide
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Chapter 10 Configuring LRE Configuring LRE Ports
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 2 5 second s, the switch does not execute rate selection to
re-establish the link . The lin k is re-established at the profile used before link loss.
The switc h choose s th e a ppr opr iate pr ofile for a n LRE i nte rface wh en i t execute s r ate sel ecti on. If line
condit ions of the L RE inte rfa ce c ha ng e, r ate sel ecti on mu st be execute d aga in.

Precedence

The rat e selectio n featur e can be app lied at both t he port level and at the switc h leve l. Profiles and
sequences have a system-defined priority level that work with rate selection to deter mine the rate for a
port or the entir e switch. Port sequen ces ha v e the highest pr iority; that is, they tak e preced ence ov er an y
other pro file or sequence . The pri ority levels, from high est to lowest, ar e as shown:
1. Port sequence: rate sel ecti on is e nabl ed o n the given port only wi th the g iven sequence.
2. Global sequence: rate selection is enabled for the entir e switch with the given sequence.
3. Port profile: rate sel ection is enable for th e give n port only w ith the given profile.
4. Global pro file: rate selection is enabled for the entire switch with the given profile.
See Table 10-1 f or the list of profiles and Table 10-2 f or the list of system-defined sequences. You can
also us e IOS c om mands or CMS to define y our own seque nces .
Note If rate selection is disabled for a port, then profiles are used.

Profile Locking

You can also use rate selection as an installation tool to lock in a particular p rofile. I n this case, you
execute rate selection only once at installatio n; afterwards, rate selection is never executed, even if one
of the four li sted e vents occur. You use the config command in privileged EXEC mode to lock the profile
chosen by rate selection. (You can enter a special EXEC command to rerun r ate selection on the
interfaces that have locked the p rofiles, as needed.)
An advantage to profile locking is that the con ver gence time during bootup is faster if a profile is locked
on an L RE po rt rath er tha n havin g to go thr oug h a p ro file seque nce .
Beginning in privileged EXEC mode, follow these steps to lock a profile in an LRE port that has rate
selection enabled:
Command Purpose
Step 1 configure terminal Enter gl obal c on figuratio n mod e.
Step 2 interface LRE- interface Enter interface configuration mode, and enter the number of the LRE port to
be co nfigured.
Step 3 rate selection profile lock Lock th e profile.
Step 4 end Retur n to privileged EXEC mode .
Step 5 show controllers lre profile details Verify the change.