Few ports in Switch behaving Strangely.

[Khundmir4cisco]

On a 2960X PoE few Ports are behaving strangely. These ports (gig 1/0/6 and gig 1/0/8) are not working when we connect an IP Phone (Cisco 8845) but are working fine when we connect a PC. We have two vlans voice and access on all ports and for these particular ports IP Phones are not working  at all even if we plug the IP Phone alone. I have also tried to keep the Voice vlan alone and it didn't work. On rest of the ports there is no issue for IP Phones. The problem is with only three ports. Configurations, switchport security and everything is same for all ports. Please help me with this. 

[Leo Laohoo]

PoE and non-PoE ports use different part of a cable. The description of the issue tells me there's a cable fault.
What IOS version is the switch running on?

[Khundmir4cisco]

I have used brand new cable and connected directly to the Switchport. It worked on maximum ports except four ports. These four ports has same config as others and I already tried to set it as default interface and configured again to see if it will work but in vain. 

Version: c2960x-universalk9-mz.152-2.E7.bin

Model: WS-C2960X-24PD-L

[Leo Laohoo · Accepted solution]

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@Khundmir4cisco wrote:

I have used brand new cable and connected directly to the Switchport.

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The version currently running supports TDR.

1.  Command:  test cable tdr interface <PORT>;

2.  Wait for approximately 5 to 7 seconds for the process to run; 

3.  Command:  show cable tdr interface <PORT>; and

4.  Post the complete output to #3.

[Khundmir4cisco]

Interface Speed Local pair Pair length        Remote pair Pair status

--------- ----- ---------- ------------------ ----------- --------------------

Gi1/0/6   auto  Pair A     1    +/- 10 meters N/A         Open

                        Pair B     1    +/- 10 meters N/A         Open

                        Pair C     2    +/- 10 meters N/A         Open

                        Pair D     2    +/- 10 meters N/A         Open

[Leo Laohoo]

Are you sure this is the correct port?
The result shows a patch cable and nothing is connected to it.

[Khundmir4cisco]

Yes. I am sure. 

When I connect a PC to the same port it will work. When I connect a telephone it will not recognize not give any PoE.

I have tested with power inline command and I see nothing in this port. Status shows not connected too.

[paul driver]

Hello

It just could be the POE of those port have failed (I am assuming these are POE ports)

Are the phone receiving the correct wattage from these ports?

Do these phone work if you attached them to other poe ports?

Have you tried defaulting the port and reconfiguring them?

[Khundmir4cisco]

Are the phone receiving the correct wattage from these ports?

// No wattage at all. It shows that the port is not connected and when I see powerinline it does not shows anything either.

Do these phone work if you attached them to other poe ports?

// Yes. Except four ports. Please note that these four ports has same config as others and I also tried to make them default but nothing new.

Have you tried defaulting the port and reconfiguring them?

// Tried but didn't work.

[paul driver · Accepted solution]

Hello

I would say then it does suggest those ports POE has failed - it does happen

[Khundmir4cisco]

You mean they fail permanently? If so, what is the solution then.

I have also reload the Switch too.

[balaji.bandi · Accepted solution]

yes the ports faulty, if the contract with Cisco raise RMA Tac case.

[Georg Pauwen · Accepted solution]

Hello,

on  a side note, check what happens if you upgrade to 15.2(4)E6 or higher. The bug below might apply;

Multiple Ports on a C2960X Stack stops providing PoE
CSCvf42171
Description
Symptom:
Some of the interfaces stops providing PoE to PD devices.

Conditions:
2960X switch.

Workaround:
Upgrade switches to 15.2(4)E6 (and higher) to prevent this failure.

Further Problem Description:
Any switches with ports failing to provide POE -- please work with TAC.

[Ondro]

Hello,

Is there any way to diagnose this issue without connecting POE device to the port?
We had issue on few switches on a production site (5 ports on 4 switches faulty). 
We cannot disconnect ports one by one and try if they work properly due we cannot afford interruptions.

Thanks in advance for your reply.
O.