04-21-2010 08:31 AM - edited 03-06-2019 10:43 AM
Hi all,
i have layer 3 switch connected to layer 2 switch .
Layer 3 ports gi 01 and gi02 have gbics and fibre
here is config of ports of layer 2
3548XL#sh run int gi0/1
Building configuration...
Current configuration:
!
interface GigabitEthernet0/1
switchport access vlan 30
end
3548XL#sh int gi0/1
GigabitEthernet0/1 is down, line protocol is down
Hardware is Gigabit Ethernet, address is 0003.6b7b.5a31 (bia 0003.6b7b.5a31)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not set
Auto-duplex , 1000Mb/s, media type is SX
output flow-control is off, input flow-control is off
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output never, output hang never
Last clearing of "show interface" counters never
Queueing strategy: fifo
Output queue 0/40, 0 drops; input queue 0/75, 0 drops
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
7 packets input, 448 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 watchdog, 0 multicast, 0 pause input
7 packets output, 448 bytes, 0 underruns
0 output errors, 0 collisions, 1 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
3548XL#
Layer 3 port status
3550SMI# sh run int gi0/1
Building configuration...
Current configuration : 98 bytes
!
interface GigabitEthernet0/1
switchport access vlan 30
switchport mode dynamic desirable
end
3550SMI#sh int gi0/1
GigabitEthernet0/1 is down, line protocol is down (notconnect)
Hardware is Gigabit Ethernet, address is 000d.28bc.fd99 (bia 000d.28bc.fd99)
MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not set
Auto-duplex, Auto-speed, link type is auto, media type is 1000BaseSX
input flow-control is off, output flow-control is desired
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: 0/75/0/0 (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
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, 1 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
3550SMI#
there is no lights on gbic ports?
any ideas?
thanks
mahesh
04-21-2010 08:50 AM
looks like a physical problem to me, have you crossed the fibres?
is there a fibre run beween the switches or are they directly connected via fibre patch cable?
have you replaced the fibre patch cable?
04-21-2010 08:57 AM
Hi
Thanks for reply.
fibre has two ends each end is labelled as B A
B is red
A is blue.
They are directly connected.Ho can i cross them?
what i can check next?
thanks
mahesh
04-22-2010 01:29 AM
Hi Mahesh,
the A and B end of the fibre must be crossed so that in switch 1 fibre A is in the left port of the fibre module and fibre B is in the right port.
On the second switch you must do the opposite, fibre B should be in the left port and fibre A should be in the right.
Switch 1 |_A__| |__B__|
Switch 2 |_B__| |__A__|
04-22-2010 03:04 PM
Hi
Thanks for reply i tried the way u mentioned but no lights on fibre ports
Light only comes when i restart the switch on gbic ports then light comes and go so this indicates that GBIC are ok and cable might be faulty?
anyother idea
thanks
mahesh
04-23-2010 01:28 AM
you could loop the fibre onto the GBIC to test the fibre cable and GBIC.
connect the same fibre into the GBIC so both A ends of the fibre connect to the same GBIC, this should bring up the GBIC connection, if it does then the GBIC and fibre are working fine, do the same with both switches
05-01-2010 10:33 AM
Hi,
thanks for reply .
i tested the cable it is fine actually i was putting the cable wrong way.
i put it right way and it worked.
also i did loop on 1 gbic port gi0/2
here is config
3550SMI# sh run int gi0/2
Building configuration...
Current configuration : 98 bytes
!
interface GigabitEthernet0/2
switchport access vlan 30
switchport mode dynamic desirable
end
also i did
3550SMI#sh int trunk
Port Mode Encapsulation Status Native vlan
Gi0/2 desirable n-isl trunking 1************************************************************************************8
do u know why it is showing as trunk type ISL ??????????
3550SMI#sh int gi0/2
GigabitEthernet0/2 is up, line protocol is up (connected)
Hardware is Gigabit Ethernet, address is 000d.28bc.fd9a (bia 000d.28bc.fd9a)
MTU 1500 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 1000BaseSX
input flow-control is off, output flow-control is off
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 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
14435 packets input, 1689928 bytes, 0 no buffer
Received 14435 broadcasts (0 multicasts)
0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
0 watchdog, 14435 multicast, 0 pause input
0 input packets with dribble condition detected
14435 packets output, 1689928 bytes, 0 underruns
0 output errors, 0 collisions, 1 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
3550SMI#sh spann
3550SMI#sh spanning-tree ?
WORD bridge group list, example 1,3-5,7,9
active Report on active interfaces only
backbonefast Show spanning tree backbonefast status
blockedports Show blocked ports
bridge Status and configuration of this bridge
detail Detailed information
inconsistentports Show inconsistent ports
interface Spanning Tree interface status and configuration
mst Multiple spanning trees
pathcost Show Spanning pathcost options
root Status and configuration of the root bridge
summary Summary of port states
uplinkfast Show spanning tree uplinkfast status
vlan VLAN Switch Spanning Trees
| Output modifiers
3550SMI#sh spanning-tree int
3550SMI#sh spanning-tree interface gi
3550SMI#sh spanning-tree interface gigabitEthernet 0/2
Vlan Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
VLAN0001 Back BLK 4 128.26 P2p
VLAN0010 Back BLK 4 128.26 P2p
VLAN0020 Back BLK 4 128.26 P2p
VLAN0030 Back BLK 4 128.26 P2p
3550SMI#
Many thanks
mahesh
05-01-2010 12:36 PM
Hi Mahesh.
3550SMI#sh int trunk
Port Mode Encapsulation Status Native vlan
Gi0/2 desirable n-isl trunking 1************************************************************************************8
do u know why it is showing as trunk type ISL ??????????
For 2950s and 3550s that is default. You can change it:
The default mode is dynamic desirable.
Have a look"
HTH
Reza
05-01-2010 01:13 PM
Hi Reza,
the fibre cable to port gi0/2 its both ends are looped to gi0/2 port.
thats my question if cable both same ends are connected to gbic why it shows as trunk ISL?
thanks
mahesh
05-01-2010 01:44 PM
Mahesh,
Because the port was already truncked. Do a "sh run int gi0/2" and see if the interface is truncked
HTH
Reza
05-02-2010 02:30 PM
Try the following command in both switches:
switchport mode trunk
switchport trunk encapsulation dot1q
switchport nonegotiate
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