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New Member

CE stop communicating to PE After Link Changeover

Dear all,

we have multiple Links in our network and Running STP to manage it.

but when link changeover, CE Stop communicating to PE until we "shut" and "no shut" on our switch port connected to CE.

if we do not do shut, no shut it takes few hours to start communicating with PE automatically.

please assist

Regards

Vikas kumar

7 REPLIES

CE stop communicating to PE After Link Changeover

Hi,

according to the symptoms, I'd guess some ARP cache problem...

Have you tried to clear arp cache on your CE instead of shut/no shut the port?

Best regards,

Milan

New Member

Re: CE stop communicating to PE After Link Changeover

Dear Milan,

Yes it is ARP Cache issue.

When client Clear ARP cache on CE it start communicating with PE.

Please assist.

Regards

Re: CE stop communicating to PE After Link Changeover

Hi,

now the questions are:

Is it an iBGP or eBGP bewteen your CE and PE?

Direct connection or multiple hops?

Is the BGP session down?

Or just packets routed to the PE are not delivered?

Which ARP entry is changed after the link changeover and why?

Best regards,

Milan

New Member

Re: CE stop communicating to PE After Link Changeover

Dear Milan,

this is Direct Connection But passing via Multiple switches And eBGP is running between CE and PE.

P2P IP configured between CE and PE.

Regards

vikas

Re: CE stop communicating to PE After Link Changeover

Hi,

so do you see the ARP entry for the PE IP address has changed on your CE after the link changeover?

If yes, you need to investigate why.

It should not change if there were a pure L2 connection (even over multiple L2 switches) between them.

Best regards,

Milan

New Member

Re: CE stop communicating to PE After Link Changeover

Dear Milan,

I have cheked MAC on PE and CE.

Both sides MAC address is correct.

Regards

CE stop communicating to PE After Link Changeover

Hi,

so what exaclty happens after the link changeover?

Is the BGP session Down or Up?

Are you able to Ping the PE from the CE?

If not, are the MAC addresses in ARP entries really correct?

Best regards,

Milan

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