Often times we have issues with cabling and don't know how to prove it. Fortunately if you are using Cisco switches you are in luck since there is a way to test the cabling using commands in the Cisco switches. Please not that this will bring that interface down, and is not recommended to be done during production hours.....
As can see from the log below:
3d00h: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to down
3d00h: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1, changed state to down
3d00h: %LINK-3-UPDOWN: Interface GigabitEthernet0/1, changed state to down
3d00h: %LINK-3-UPDOWN: Interface GigabitEthernet0/1, changed state to up
3d00h: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1, changed state to up
3d00h: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to up
How do we do that you ask? Well here goes:
Test_Switch01#test cable-diagnostics tdr interface GigabitEthernet0/1
To see the results:
Hope this will help you tell the facilities guys to check the cabling...
As can see from the log below:
3d00h: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to down
3d00h: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1, changed state to down
3d00h: %LINK-3-UPDOWN: Interface GigabitEthernet0/1, changed state to down
3d00h: %LINK-3-UPDOWN: Interface GigabitEthernet0/1, changed state to up
3d00h: %LINEPROTO-5-UPDOWN: Line protocol on Interface GigabitEthernet0/1, changed state to up
3d00h: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan1, changed state to up
How do we do that you ask? Well here goes:
Test_Switch01#test cable-diagnostics tdr interface GigabitEthernet0/1
To see the results:
Test_Switch01#sh cable-diagnostics tdr int gigabitEthernet 0/1
TDR test last run on: March 04 00:36:40
Interface Speed Local pair Pair length Remote pair Pair status
--------- ----- ---------- ------------------ ----------- ------------- -------
Gi0/1 100M Pair A 0 +/- 4 meters Pair B Normal
Pair B 0 +/- 4 meters Pair A Normal
Pair C 1 +/- 4 meters Pair C Short
Pair D 2 +/- 4 meters Pair D Short
Test_Switch01#
Hope this will help you tell the facilities guys to check the cabling...