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HELP configure FR PVC on MGX8850

have customer pvc's all on CWM's default values like IBS, Bc, Be, VC, ECN, DE thresholds. how do i customize values say for;

a) 64 AR, 32 CIR

b) 128 AR, 64 CIR

c) 256 AR, 128 CIR or 256 CIR.

are there formulas to be able to compute.

keep on getting DE's and DF's even traffic doesn't exceed CIR.

Cisco Employee

Re: HELP configure FR PVC on MGX8850

From CWM you can use the connection manager and edit your PVC's. However, I do most of my work on the command line, and from there, you can use commands like cnfcon for the CIR, and cnfchanfst if you are using foresight. Finally, you can use the command xcnfchan for just about anything.

For your specific options, you never need to configure AR. That will always match the port speed.

Now, if you want to set PIR, you can enable foresight and use the command cnfchanfst.


1. cnfchanfst 1 84 167 167

2. cnfchanfst 1 167 334 334

3a. cnfchanfst 1 334 667 667

3b. cnfchanfst 1 667 667 667

These numbers may appear strange, but they are in

cells/sec. To convert from bits/sec to cells/sec, take the bits/s number and devide by (8x48=384)

You will have to do this on both FRSM's, and you might have to make a change to the connection on the BPX, if indeed you use BPX's to connect your MGX's.