Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

GRE Tunnel

I have 2 GRE Tunnels bulit on my serial interface. One of my tunnels is showing as line protocol down. It is the same on the peer end too. How do i troubleshoot further on this?

Appreciate your help on this.

Regards

Navneet

1 ACCEPTED SOLUTION
6 REPLIES

Re: GRE Tunnel

hi Navneet,

just check it out your tunnel interface with command show interface tunnel x. and check it out the keepalive retries counter next to keepalive set. to make your tunnel up it must be zero or less then the configure time. if it is greater than your set timer then there must be no exchange of keepalive which make your tunnel interface protocol down.

hope this will help you

rate the post if it helps

regards

Devang

Re: GRE Tunnel

Is the destination reachable from both peers?

int tunnel 1

tunnel source IP

tunnel destination IP!!!! can you ping this IP?

Please let us know,

vlad

New Member

Re: GRE Tunnel

Thanx for the Reply.

The Tunnel has come back up now. I needed to know a few things with regards to the tunnel troubleshooting.

1) What is the reason for tunnel flaps, even if the interface on which it is built is up and working fine?

2) is there any documentation for GRE and GRE over IPSEC tunnels.

thanking you in advance.

Regards

Navneet

New Member

Re: GRE Tunnel

Thnx for the Links Devang. It really helped.

Cheers

Navneet

Re: GRE Tunnel

hi Navneet

thanks to you also for giving rating...and with the help of your rating i completed my 100 points.

thanking you again

regards

Devang

276
Views
0
Helpful
6
Replies