Tunnel20 is up, line protocol is up
  Hardware is Tunnel
  Description: 5MB Fiber Link 
  Internet address is x.x.x.x/30
  MTU 1514 bytes, BW 5000 Kbit, DLY 500000 usec,
     reliability 255/255, txload 35/255, rxload 14/255
  Encapsulation TUNNEL, loopback not set
  Keepalive set (5 sec), retries 3
  Tunnel source x.x.x.x., destination x.x.x.x
  Tunnel protocol/transport GRE/IP
    Key 0xC9, sequencing disabled
    Checksumming of packets disabled
  Tunnel TTL 255
  Fast tunneling enabled
  Tunnel transmit bandwidth 8000 (kbps)
  Tunnel receive bandwidth 8000 (kbps)
  Last input 00:00:00, output 00:00:00, output hang never
  Last clearing of "show interface" counters never
  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 1202
  Queueing strategy: fifo
  Output queue: 0/0 (size/max)
  5 minute input rate 283000 bits/sec, 226 packets/sec
  5 minute output rate 688000 bits/sec, 270 packets/sec
 49409747 packets input, 1785360220 bytes, 0 no buffer
     Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
     62245585 packets output, 1343587855 bytes, 0 underruns
     0 output errors, 0 collisions, 0 interface resets
     0 output buffer failures, 0 output buffers swapped out

sh run int tun 20

Current configuration : 286 bytes
!
interface Tunnel20
 description 5MB Fiber Link
 bandwidth 5000
 ip address x.x.x.x 255.255.255.252
 ip mtu 1400
 ip ospf cost 11
 keepalive 5 3
 tunnel source x.x.x.x
 tunnel destination x.x.x.x
 tunnel key 201
end