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New Member

Router cannot communicate

We have serveral devices (Cisco 7609 and 3750s) connecting to each other

through SONET ring over vlan 802. The cisco 7609 is not able to

ping one of 3750s . They were working before but stopped suddenly

Both 7609 and 3750 can communicate with other 3750s on the same vlan fine. On 7609

entry for ip for this 3750 is "incomplete". config seems fine as it worked before and there is no change and we even tried swapping with a new switch but it did not work


Re: Router cannot communicate

did you try clearing the ARP table on the 7609 ?

New Member

Re: Router cannot communicate

yes i did clear the arp table and it still wont show up

Cisco Employee

Re: Router cannot communicate

Hello Devi,

If you see "incomplete" for the ARP Entry, this is most likely the router is sending a ARP Request to the 3750 and is not getting a ARP Reply back.

If you have already cleared the ARP and still does not work, I would suggest that you do a "Deb arp" on both the 7609 and 3750 and see if you are seeing ARP Request and Reply packets. Based on the outcome of your testing, you need to focus on where the issue is. Maybe, what you are running into is a MAC Address limitation on the Chassis itself or the SP Network.

Also, it is recommended that you run the debugs after business hours.



*Pls rate if it helps*

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