08-11-2008 05:38 AM - edited 03-06-2019 12:43 AM
I have a fiber ring using 1 3548xl, 2 3512xl, a 3508, and the gbic card for a 6509. One link in the loop is "state changed to up" for a few seconds, then down again, and repeats. Is this normal for a loop in this configuration?
08-11-2008 06:46 AM
Apparently the network is not stable.
Are you using UDLD? Is your STP converging again and again too? Do you see another interface bouncing as well?
Thanks.
08-11-2008 07:07 AM
I've posted my "sh udld" from the switch that is showing:
Interface Gi0/1
Port enable configuration setting: Follows global setting
Operational enable state: Disabled
Current bidirectional state: Unknown
Message interval: 7
Message timer: 1
Current operational state: Disabled and link down
Time out interval: 5
Time out timer: 0
Restart counter: 0
Neighbors counter: 0
Probe counter: 4
No multiple neighbors detected
Current pool id: 1
No neighbor cache information stored
Also, I'm not showing any of the other interfaces on the loop doing the "UP/Down" bounce.
Another note: This was working. About a year ago our fiber was cut, and the loop held. Could this be caused by bad GBICs? I've tested the fiber, it shows good.
I'm guessing by your post that I should see this link active all the time. Is that correct?
Thanks for looking into this with me.
08-11-2008 07:09 AM
post a show interface gx/x for the switch that is bouncing, post a show spanning-tree as well
08-11-2008 07:20 AM
I'm posting the sh int g0/1 twice, just to show the state of things in both the up and down states.
Thanks.
CarterBldg#sh int g0/1
GigabitEthernet0/1 is down, line protocol is down
Hardware is Gigabit Ethernet, address is 0002.4b10.b3cd (bia 0002.4b10.b3cd)
MTU 1500 bytes, BW 0 Kbit, DLY 0 usec,
reliability 255/255, txload 255/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not set
Auto-duplex , link type is autonegotiation, 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 00:00:03, 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 7000 bits/sec, 7 packets/sec
1 packets input, 64 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
1850656 packets output, 206806141 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
CarterBldg#
CarterBldg#sh int g0/1
GigabitEthernet0/1 is up, line protocol is up
Hardware is Gigabit Ethernet, address is 0002.4b10.b3cd (bia 0002.4b10.b3cd)
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,
reliability 255/255, txload 255/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive not set
Auto-duplex (Full), link type is autonegotiation, 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 00:00:00, 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 8000 bits/sec, 6 packets/sec
1 packets input, 64 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
1850709 packets output, 206814485 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
CarterBldg#sh spanning-tree
Spanning tree 1 is executing the IEEE compatible Spanning Tree protocol
Bridge Identifier has priority 32768, address 0002.4b10.b3c0
Configured hello time 2, max age 20, forward delay 15
Current root has priority 5, address 00d0.021f.ac00
Root port is 39, cost of root path is 3016
Topology change flag not set, detected flag not set, changes 2
Times: hold 1, topology change 35, notification 2
hello 2, max age 20, forward delay 15
Timers: hello 0, topology change 0, notification 0
Interface Gi0/1 (port 31) in Spanning tree 1 is down
Port path cost 4, Port priority 128
Designated root has priority 5, address 00d0.021f.ac00
Designated bridge has priority 32768, address 0002.4b10.b3c0
Designated port is 31, path cost 3016
Timers: message age 0, forward delay 0, hold 0
BPDU: sent 31408, received 0
Interface Gi0/2 (port 39) in Spanning tree 1 is FORWARDING
Port path cost 4, Port priority 128
Designated root has priority 5, address 00d0.021f.ac00
Designated bridge has priority 32768, address 0009.e8e1.f5c0
Designated port is 23, path cost 3012
Timers: message age 0, forward delay 0, hold 0
BPDU: sent 1, received 126197
08-11-2008 07:29 AM
find your root bridge, it's mac is 00d0.021f.ac00. check its log and look at the show spanning-tree outputs.
08-11-2008 07:57 AM
I've attached the sh spanning-tree info because it's quite a bit different than what I get on the other switches...
VLAN0001 is associated with that mac, although we usually disable that vlan on our network. The fast ethernet ports are on vlan0004 and the administrative network is vlan0202.
The logs for that switch show nothing about the fiber ports, only various fastethers connecting and disconnecting.
Any ideas? Thanks again.
VLAN0001
Spanning tree enabled protocol ieee
Root ID Priority 5
Address 00d0.021f.ac00
Cost 3004
Port 49 (GigabitEthernet0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 49153 (priority 49152 sys-id-ext 1)
Address 0015.f974.5180
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300
Uplinkfast enabled
Interface Role Sts Cost Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi0/1 Root FWD 3004 128.49 P2p
Gi0/2 Desg FWD 3004 128.50 P2p
VLAN0004
Spanning tree enabled protocol ieee
Root ID Priority 32768
Address 0002.4b10.b3c3
Cost 3012
Port 50 (GigabitEthernet0/2)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 49156 (priority 49152 sys-id-ext 4)
Address 0015.f974.5180
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300
Uplinkfast enabled
Interface Role Sts Cost Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Gi0/1 Desg FWD 3004 128.49 P2p
Gi0/2 Root FWD 3004 128.50 P2p
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