GRE tunnel can't ping each other

[Mary]

I have router R1,R2 connected with f0/0, R2,R3 connected with f0/1, I didn't use any dynamic route or static route, then I configure GRE, but in R1 Ican't ping 13.0.0.3, how to correct? thanks

R1:

interface Loopback0
ip address 150.1.1.1 255.255.255.0
!
interface Tunnel13
ip address 13.0.0.1 255.255.255.0
tunnel source 155.1.12.1
tunnel destination 155.1.23.3
!
interface FastEthernet0/0
ip address 155.1.12.1 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto

+++++++++++++++++++

R2: 

interface Loopback0
ip address 150.1.2.2 255.255.255.0
!
interface FastEthernet0/0
ip address 155.1.12.2 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
ip address 155.1.23.2 255.255.255.0
duplex auto
speed auto
!

++++++++++++++++++

R3:

interface Loopback0
ip address 150.1.3.3 255.255.255.0
!
interface Tunnel13
ip address 13.0.0.3 255.255.255.0
tunnel source 155.1.23.3
tunnel destination 155.1.12.1
!
interface FastEthernet0/0
no ip address
shutdown
duplex auto
speed auto
!
interface FastEthernet0/1
ip address 155.1.23.3 255.255.255.0
duplex auto
speed auto
!

[Support07]

Hi,

you have to configure static ip route like this :

R1 -> ip route 155.1.23.0 255.255.255.0 155.1.12.2

R3 -> ip route 155.1.12.0 255.255.255.0 155.1.23.2

Then your tunnel will be up, and reachable.