Gre Tunnel from Site 1 to 2 has no connection.

[Lost & Found]

Hi.

Ive tried to configure Gre tunnel on out site 1 and 2 but both site has no connection. 

All tunnel interface status is UP/UP

from isp router 2 ip can ping the int tunnel IP but ISP router 1 can't ping it's own tunnel address.

Is it fine to run with s0/0 interface?

Router 2 - 2800 and router 1 - 2600

Do i need to setup OSPF to ping r1-r2? or just static configuration?

Please see the attached photo for the configuration.

thanks

[Robert Hillcoat]

The configuration of your IP address is wrong. 

One side should be 10.10.1.1 and the other side should be 10.10.1.2, according to your picture they have the same address on both sides. 

[Richard Burts]

The duplicate IP addresses on the tunnel are certainly a problem. And the address of 300.1.1.222 is certainly not going to work. But assuming that the addresses given are disguised and not the real addresses that you are using it is perhaps not such a big deal.

I agree with Joseph that the first thing to do is to verify whether each router is able to ping to the outside IP address of its peer router. This is the biggest problem that most people face when attempting to set up GRE tunnels. You have provided only parts of the config and there could be other issues which we can not yet see. But verifying external connectivity is the first step in troubleshooting.

HTH

Rick

[Lost & Found]

Hi,

Sorry I typed the wrong ip address on diagram.

but on Router configuration it's 10.10.1.1 and 10.10.1.2.

[Joseph W. Doherty]

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Posting

Some GRE implementations report up/up even though there's no logical connectivity (enabling keep alives will bring the tunnel down).

Can both routers ping the far side's external IP?  (Outside of the tunnel.)

[Lost & Found]

Hi,

2600 Router can't support keepalive.

r1-r2 yes

r2-r1 no

I'll check if ICMP on r1 is disable.

thanks

[Richard Burts]

I am surprised that the 2600 can not support GRE keepalive. But that is nice to have but not important in solving this problem.

I am surprised that R1 can ping R2 but R2 can not ping R1. But if that is the case then it certainly is the reason why the GRE tunnel is not working. You might want to try a traceroute between the routers and see if anything unexpected turns up in the traceroute.

HTH

Rick

[Lost & Found]

Hi,

Now I can R1 to R2 and R2 to R1. but my tunnel is still not working.

all int is up/up

R1#show int tunnel 1

Tunnel1 is up, line protocol is up

  Hardware is Tunnel

  Internet address is 172.16.1.1/24

  MTU 17916 bytes, BW 100 Kbit/sec, DLY 50000 usec,

     reliability 255/255, txload 1/255, rxload 1/255

  Encapsulation TUNNEL, loopback not set

  Keepalive not set

  Tunnel linestate evaluation up

  Tunnel source XXXX (Serial0/0/0), destination XXXX

   Tunnel Subblocks:

      src-track:

         Tunnel1 source tracking subblock associated with Serial0/0/0

          Set of tunnels with source Serial0/0/0, 1 member (includes iterators), on interface <OK>

  Tunnel protocol/transport GRE/IP

R2#

Tunnel1 is up, line protocol is up

  Hardware is Tunnel

  Internet address is 172.16.1.2/24

  MTU 17916 bytes, BW 100 Kbit/sec, DLY 50000 usec,

     reliability 255/255, txload 1/255, rxload 1/255

  Encapsulation TUNNEL, loopback not set

  Keepalive not set

  Tunnel source XXXX (GigabitEthernet0/1), destination XXXX

   Tunnel Subblocks:

      src-track:

         Tunnel1 source tracking subblock associated with GigabitEthernet0/1

          Set of tunnels with source GigabitEthernet0/1, 1 member (includes iter

ators), on interface <OK>

  Tunnel protocol/transport GRE/IP

thanks

[Richard Burts]

I am glad that you have made progress with this issue. Obviously some things have changed. So would you give us a fresh copy of the current configurations?

Also can you post the output of R1 pinging R2 tunnel destination and specifying the source address to be the tunnel source. And post the output of R2 pinging R1 tunnel destination and specifying the source address to be the tunnel source.

HTH

Rick

[Predrag Jovic]

Are you sure that your interface s0/0 IP address is 300.1.1.222?

:)