ppp multilink

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Jun 16th, 2009
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I have configured MLP over PPPoE and ADSL. Though the

connectivity is up, Interleaving is always reports as disabled on BRAS while CPE is enabled.

The ppp session also goes up/down about every 2 minutes and i think due this problem.

Without interleaving, everything is ok, ppp multilink is stable.

Please see the config, show output and debugs below.

Any help?



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slmansfield Tue, 06/16/2009 - 12:43
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I'll just take a stab at this. Based on this document, it indicates that if you are configuring interleaving on a virtual template interface you need to include the global config statement (assuming the number has to match your virtual-template interface number):

multilink Virtual-Template6


From your configuration I can't tell if you've included this statement.

For the flapping, you might try some additional PPP debugs.

bbaillie Tue, 06/16/2009 - 15:43
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Hi Milko,

There appears to be two multilink sessions using the same virtual template. Multilink will have a problem differentiating between them. Here is what I have done in the past, on the interface define each interface with a different endpoint discriminator string, this is local to the router and doesn't need to match the other end of the link.

The command is "ppp multilink endpoint string adsl-one" where adsl-one is the string to keep locally unique, maybe use adsl-two for the other interface. This will stop the flapping of the multilink interfaces.

I strongly suspect that due to the default definition of the bandwidth parameter for a multilink interface being a T1 (1.544 Mbs) you may want to correctly define the bandwidth parameter as this determines the fragment size and whether interleaving actually has any noticable effect.

The previous post has the correct information, follow the link Susan provided and search for "Changing the Default Endpoint Discriminator".




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