Cisco switch not acting right
On a new install of a WS-C2960S-48TS-L. The switch has 4 SFP ports. I have other Cisco switches with the same SFP port module this one has and am fimiliar with them. The documentation claims I am using the correct SFP module.
I installed a new GLC-SX-MM module in one of the ports and connected it to a SFP port on my WS-C2960G-24TC-L. Here is what happens:
C2960S (new) - Gi1/0/50 1000 BaseSX SFP Status: Port is disabled.
C2960G (existing) - Gi0/23 1000 Base SX SFP Status: Link up Speed 1000 mbps Duplex Full.
I can't find any way to get it to work. I have disabled and enabled the port without luck. I have used different SFP modules in different ports. Same result.
Is the switch defective?
I installed a new GLC-SX-MM module in one of the ports and connected it to a SFP port on my WS-C2960G-24TC-L. Here is what happens:
C2960S (new) - Gi1/0/50 1000 BaseSX SFP Status: Port is disabled.
C2960G (existing) - Gi0/23 1000 Base SX SFP Status: Link up Speed 1000 mbps Duplex Full.
I can't find any way to get it to work. I have disabled and enabled the port without luck. I have used different SFP modules in different ports. Same result.
Is the switch defective?
ASKER
CS-G-830-1>sh spanning-tree
VLAN0001
Spanning tree enabled protocol ieee
Root ID Priority 32768
Address 0009.5bb3.c8c9
Cost 20004
Port 1 (GigabitEthernet1/0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32769 (priority 32768 sys-id-ext 1)
Address 5897.1ea7.5000
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec
Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------
Gi1/0/1 Root FWD 4 128.1 P2p
Gi1/0/8 Desg FWD 4 128.8 P2p
Gi1/0/14 Desg FWD 4 128.14 P2p
Gi1/0/30 Desg FWD 4 128.30 P2p
Gi1/0/33 Desg FWD 4 128.33 P2p
Gi1/0/34 Desg FWD 4 128.34 P2p
Gi1/0/35 Desg FWD 4 128.35 P2p
Gi1/0/47 Desg FWD 4 128.47 P2p
Gi1/0/48 Desg FWD 4 128.48 P2p
Gi1/0/50 Altn BLK 4 128.50 P2p
VLAN0001
Spanning tree enabled protocol ieee
Root ID Priority 32768
Address 0009.5bb3.c8c9
Cost 20004
Port 1 (GigabitEthernet1/0/1)
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Bridge ID Priority 32769 (priority 32768 sys-id-ext 1)
Address 5897.1ea7.5000
Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
Aging Time 300 sec
Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------
Gi1/0/1 Root FWD 4 128.1 P2p
Gi1/0/8 Desg FWD 4 128.8 P2p
Gi1/0/14 Desg FWD 4 128.14 P2p
Gi1/0/30 Desg FWD 4 128.30 P2p
Gi1/0/33 Desg FWD 4 128.33 P2p
Gi1/0/34 Desg FWD 4 128.34 P2p
Gi1/0/35 Desg FWD 4 128.35 P2p
Gi1/0/47 Desg FWD 4 128.47 P2p
Gi1/0/48 Desg FWD 4 128.48 P2p
Gi1/0/50 Altn BLK 4 128.50 P2p
It's blocking - BLK tells us that.
Before you unblock it, find out why it's doing this - and by that I mean find out what loop you're being protected from by spanning-tree.
If you want redundant links, etc. I would suggest configuring the links as Etherchannel.
Before you unblock it, find out why it's doing this - and by that I mean find out what loop you're being protected from by spanning-tree.
If you want redundant links, etc. I would suggest configuring the links as Etherchannel.
ASKER
So you are saying it is protecting itself, probably from loopback? I have no other direct connections to the other switch. There is a third switch involved that provides an indirect link. Could this be the problem?
How do I unblock it?
How do I unblock it?
ASKER CERTIFIED SOLUTION
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ASKER
OK, so that confirms the third switch is the problem. Thanks for your help.
You're welco-oh wait, you weren't thanking me....guess I gave you zero info that helped. Good times!
Yeah... These points should go to rharland2009.
ASKER
Oh, I am so sorry. I wasn't paying attention. How do we get the points to the correct person?
Don't sweat it...I was just being snarky. Glad you got your gear rockin.
Do a sh spanning-tree blockedports while the interface in question is connected.
Do a sh spanning-tree gi1/0/50 as well.