OSPF: MTU XR vs IOS

Kejadian unik ketika troubleshoot link, saat itu OSPF antara ASR9K dan ME3750 tidak mau establish dengan benar. Si IOS XR menampilkan proses OSPF (Exstart/Exchange). Padahal saat show interface gi1/1/1 di sisi C3750, si mtu bernilai 9000.

C3750#sh int gi1/1/2
GigabitEthernet1/1/2 is up, line protocol is up (connected)
Hardware is Gigabit Ethernet, address is xxx.yyyy
Description: Link to ASR9010
Internet address is xx.xx.xx.xy/30
MTU 9000 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not set
Full-duplex, 1000Mb/s, link type is auto, media type is 1000BaseZX SFP
input flow-control is off, output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:00, output 00:00:00, output hang never
Last clearing of “show interface” counters 40w6d
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
30 second input rate 5000 bits/sec, 6 packets/sec
30 second output rate 28000 bits/sec, 39 packets/sec
23005375103 packets input, 7147388758249 bytes, 0 no buffer
Received 15814942 broadcasts (0 IP multicasts)
0 runts, 0 giants, 0 throttles
1 input errors, 1 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 15814937 multicast, 0 pause input
0 input packets with dribble condition detected
7178930024 packets output, 5735711202294 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier, 0 PAUSE output
0 output buffer failures, 0 output buffers swapped out

C3750#

di sisi ASr9010, juga dibuat mtu=9000. Ternyata, Continue reading “OSPF: MTU XR vs IOS”