Cisco C9300 switch 25G interface can't up, TW1/1/2 is configure interface which connect to C9500 switch 25G interface,
TW1/1/1 connect to TW2/1/1 is not configure interface also can't up,
what special configure need under this interface to bring it up.
configure as below (seems it can not detect connect cable)
interface Port-channel1
description To_C9500_TBITCSW01
switchport mode trunk
interface FortyGigabitEthernet2/1/1
!
interface FortyGigabitEthernet2/1/2
!
interface TwentyFiveGigE2/1/1
!
interface TwentyFiveGigE2/1/2
switchport mode trunk
channel-protocol pagp
channel-group 1 mode auto
interface FortyGigabitEthernet1/1/1
!
interface FortyGigabitEthernet1/1/2
!
interface TwentyFiveGigE1/1/1
!
interface TwentyFiveGigE1/1/2
switchport mode trunk
channel-protocol pagp
channel-group 1 mode auto
TwentyFiveGigE1/1/2 is down, line protocol is down (notconnect)
Hardware is Twenty Five Gigabit Ethernet, address is 4cbc.489c.ae40 (bia 4cbc.489c.ae40)
MTU 1500 bytes, BW 25000000 Kbit/sec, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not set
Full-duplex, 25Gb/s, link type is auto, media type is SFP-25GBase-SR
Fec is auto
input flow-control is on, output flow-control is unsupported
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output never, output hang never
Last clearing of "show interface" counters never
Input queue: 0/2000/0/0 (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
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts (0 multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 0 multicast, 0 pause input
0 input packets with dribble condition detected
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 2 interface resets
0 unknown protocol drops
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
