Hi Adnane,
This seems to be a duplicated post, you posted the same question in other thread:
https://supportforums.cisco.com/message/3644834#3644834
As I mentioned there in reply to your question, if you are trying to configure 2 multilinks between the same pair of the routers, you should keep in mind that multilink needs to identify how to differentiate between bundles - so you need to identify the member links of the bundle.
In standard configuration without authentication, the differentiation method is to use an endpoint dicriminator for the serial links. Endpoint discriminators are locally specific to the router, so there is no need to make them match on source and target router. And, of course, if more than one interface is assigned to the same multilink bundle they must have the same endpoint discriminator value.
Here is a small example of how it looks like:
interface Serial 1/0/0:1
encapsulation ppp
ip route-cache cef
ppp multilink
multilink-group 1
ppp multilink endpoint string multi1
interface Serial 1/0/1:1
encapsulation ppp
ip route-cache cef
ppp multilink
multilink-group 1
ppp multilink endpoint string multi1
For multilink2 you should use different endpoint string, e.g. "multi2".
The other way to distinguish the bundles is to use multilink with authentication, which requires ppp chap and the example of which you can see here:
http://www.cisco.com/en/US/tech/tk713/tk507/technologies_configuration_example09186a0080093c1d.shtml
Kind Regards,
Ivan
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Kind Regards,
Ivan
