I am trying to setup trunk between two 3550s. I configured the trunk one each switch as usual but the port always show interface is down and notconnected (The cable is good).
The IOS version is 12.1(22)EA1a.
switchport trunk encapsulation dot1q
switchport mode trunk
Switch#sh int f0/24
FastEthernet0/24 is down, line protocol is down (notconnect)
Hardware is Fast Ethernet, address is 000e.84f6.3618 (bia 000e.84f6.3618)
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)
Auto-duplex, Auto-speed, media type is 100BaseTX
input flow-control is off, output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output 00:10:55, 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 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
I was thinking on trunk encapsulation and tried both dot1q and isl were all not working. I even removed the trunk setting and put them on same VLAN, the ports still show down and notconnected. This is weird to me. When I connected any one of 3550 with other device like ASA5520 with trunk setting, it works fine.
Is there special setting for configuring trunk between 3550s?
Thank you in advance.