Hello,
I have the following issue with two switches connected through a 100Base-FX link. On one side there is a WS-C2950C-24 (fixed configuration switch with two native 100Base-FX ports) and on the other side there is a WS-C2960-24TC-L using a 100Base-FX SFP module. The problem is that on the 2950 the port is operating at 100Mpbs/Full-Duplex but at the 2960 the port is operating at 100Mbps/Half-Duplex. I am not being able to set duplex mode to full from interface configuration because the command is neither available nor hidden, the IOS version is 12.2(25)SEE2.
As you can see from the show interface command, the 2950 side is working as expected but on the 2960 side is working half-duplex:
SW_2950#sh inter faste0/25
FastEthernet0/25 is up, line protocol is up (connected)
Hardware is Fast Ethernet, address is 0017.0efe.6dd9 (bia 0017.0efe.6dd9)
Description: Enlace a Pintado
MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 100Mb/s, media type is 100BaseFX
input flow-control is unsupported output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:00, output 00:00:01, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 106000 bits/sec, 54 packets/sec
5 minute output rate 106000 bits/sec, 55 packets/sec
851275 packets input, 170936567 bytes, 0 no buffer
Received 93676 broadcasts (0 multicast)
0 runts, 0 giants, 0 throttles
713 input errors, 713 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 90199 multicast, 0 pause input
0 input packets with dribble condition detected
890989 packets output, 205010324 bytes, 0 underruns
0 output errors, 0 collisions, 2 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
Sw_2960#sh inter gi0/1
GigabitEthernet0/1 is up, line protocol is up (connected)
Hardware is Gigabit Ethernet, address is 0019.e718.a519 (bia 0019.e718.a519)
Description: Enlace a MDF Galvanizado
MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not set
Half-duplex, 100Mb/s, link type is auto, media type is 100BaseFX SFP
input flow-control is off, output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:01, 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: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 92000 bits/sec, 54 packets/sec
5 minute output rate 90000 bits/sec, 52 packets/sec
902545 packets input, 207570936 bytes, 0 no buffer
Received 121948 broadcasts (0 multicast)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 86423 multicast, 0 pause input
0 input packets with dribble condition detected
863562 packets output, 173504349 bytes, 0 underruns
0 output errors, 298 collisions, 1 interface resets
0 babbles, 740 late collision, 0 deferred
0 lost carrier, 0 no carrier, 0 PAUSE output
0 output buffer failures, 0 output buffers swapped out
Is there any way to force the 2960 to operate full duplex?
I also noticed that the interface is referenced as "gigabitethernet" from CLI eventhough the 100Base-FX is recognized at the show interface level.
