Routers connected via serial subinterfaces(for non VPN internet service in a mpls network)

Question

I have conected two cisco 7200 routes via one serial interface.
I am going to create two subinterfaces in each of them assign them IP address and connect them via (two BGP neighborship)
the fact is that they cannot even ping eachother though they are directly connected .
1. interfaces are no shut
2.L2 protocol is HDLS on both sides
3.the IPs are in the same subnets .
the question is how to connect two routers with serial sub-interfaces.?
this is my config on both routers , only the IPs are different:
int ser 1/0
no shut
encapsulation hdlc
clock rate 64000
int ser 1/0.1
subif)#ip add a.b.c.d x.x.x.x

Answer 1

Hello Gabriel,
Instead of using the HDLC, use frame-relay encap. Make one side as DCE. Use same DLCI on both sides.
R4#sh run int se2/0
Building configuration...
Current configuration : 96 bytes
interface Serial2/0
no ip address
encapsulation frame-relay
frame-relay intf-type dce
end
R4#sh run int se2/0.1
Building configuration...
Current configuration : 113 bytes
interface Serial2/0.1 point-to-point
ip address 1.1.1.1 255.255.255.0
frame-relay interface-dlci 100  
end
R4#ping 1.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds:
Success rate is 100 percent (5/5), round-trip min/avg/max = 40/40/44 ms
R4#ping 1.1.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.1.2, timeout is 2 seconds:
Success rate is 100 percent (5/5), round-trip min/avg/max = 20/22/32 ms
R4#sh run | i swit
frame-relay switching
R4#
R5#sh run int se2/0
Building configuration...
Current configuration : 69 bytes
interface Serial2/0
no ip address
encapsulation frame-relay
end
R5#sh run int se2/0.1
Building configuration...
Current configuration : 113 bytes
interface Serial2/0.1 point-to-point
ip address 1.1.1.2 255.255.255.0
frame-relay interface-dlci 100  
end
R5#ping 1.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds:
Success rate is 100 percent (5/5), round-trip min/avg/max = 20/21/24 ms
R5#ping 1.1.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.1.2, timeout is 2 seconds:
Success rate is 100 percent (5/5), round-trip min/avg/max = 36/40/44 ms
R5#
Hope this helps.
Regards,
Imran