Solved: 2610XM encapsulation failed

wgranada1 · ‎06-09-2008

I was running a debug command on my router as a user is complaining that he has problem connecting to a server. I asked the user to do a ping from the source to the destination while i ran debug. On the debugs I saw:

6w6d: IP: s=205.248.197.50 (Serial0/0), d=172.18.116.2 (FastEthernet0/0), len 284, encapsulation failed

6w6d: ICMP type=8, code=0

trying to find out what that means but if anyone knows off the top of their head please let me know. Thank you in advance

Richard Burts · ‎06-09-2008

Warren

In my experience of things like this the encapsulation failed error is frequently caused because there is no entry in the ARP table for the destination address. Can you get that person to test again, and if it fails again then check and see if there is an ARP entry for address 172.18.116.2 on interface FastEthernet0/0?

[edit] is it possible that there is a typo in some digit in one of the octets and that this address is really not the correct address for the server?

HTH

Rick

HTH

Rick

View solution in original post

Pravin Phadte · ‎06-09-2008

Hi,

I had seen this error and it was due to the nat configured on router.

Still not sure if its the same kind of setup for you.

Regards,

Pravin

Richard Burts · ‎06-09-2008

Warren

In my experience of things like this the encapsulation failed error is frequently caused because there is no entry in the ARP table for the destination address. Can you get that person to test again, and if it fails again then check and see if there is an ARP entry for address 172.18.116.2 on interface FastEthernet0/0?

[edit] is it possible that there is a typo in some digit in one of the octets and that this address is really not the correct address for the server?

HTH

Rick

HTH

Rick

wgranada1 · ‎06-09-2008

Hi Rick

You are absolutly correct I found that the address wasn't in the arp table like you mentioned....thank you sir!!!!!!

wgranada1 · ‎06-09-2008

Thank you for the post but I was able to find the issue, issue is is on the fastethernet side when I looked at the arp table for the the server I didn't see it in the arp table thus the encapsulation failed.

Richard Burts · ‎06-09-2008

Warren

I am glad that you were able to identify the cause of the problem. Thank you for using the rating system to indicate that your problem was solved (and thanks for the rating). It makes the forum more useful when people can read about a problem and can know that there was a solution to the problem.

The forum is an excellent place to learn about Cisco networking. I encourage you to continue your participation in the forum.

HTH

Rick

HTH

Rick

Pravin Phadte · ‎06-09-2008

Thats great.

I know why this can happen now.