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No link light between cisco switch trunk ports, using crossover cable

No link light between cisco switch trunk ports, using crossover cable. Please see below and thanks for your help.

48_port_switch#sh ip int brief
Interface              IP-Address      OK? Method Status                Protocol
Vlan1                  192.168.5.2     YES manual up                    up
Vlan10                 192.168.10.2    YES NVRAM  up                    up
Vlan20                 192.168.20.2    YES NVRAM  up                    down
FastEthernet0/1        unassigned      YES unset  down                  down

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48_port_switch#sh int fa0/1 switchport
Name: Fa0/1
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: down
Administrative Trunking Encapsulation: dot1q
Negotiation of Trunking: On
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Administrative Native VLAN tagging: enabled
Voice VLAN: none
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Administrative private-vlan trunk native VLAN: none
Administrative private-vlan trunk Native VLAN tagging: enabled
Administrative private-vlan trunk encapsulation: dot1q
Administrative private-vlan trunk normal VLANs: none
Administrative private-vlan trunk associations: none
Administrative private-vlan trunk mappings: none
Operational private-vlan: none
Trunking VLANs Enabled: 1,10,20
Pruning VLANs Enabled: 2-1001
Capture Mode Disabled
Capture VLANs Allowed: ALL

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TestSwitch#sh ip int brief
Interface              IP-Address      OK? Method Status                Protocol
Vlan1                  unassigned      YES NVRAM  up                    down
Vlan50                 10.1.50.10      YES NVRAM  down                  down
Vlan100                10.1.100.10     YES NVRAM  down                  down
FastEthernet0/1        unassigned      YES unset  down                  down

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TestSwitch#sh int fa0/1 switchport
Name: Fa0/1
Switchport: Enabled
Administrative Mode: trunk
Operational Mode: down
Administrative Trunking Encapsulation: dot1q
Negotiation of Trunking: On
Access Mode VLAN: 1 (default)
Trunking Native Mode VLAN: 1 (default)
Administrative Native VLAN tagging: enabled
Voice VLAN: none
Administrative private-vlan host-association: none
Administrative private-vlan mapping: none
Administrative private-vlan trunk native VLAN: none
Administrative private-vlan trunk Native VLAN tagging: enabled
Administrative private-vlan trunk encapsulation: dot1q
Administrative private-vlan trunk normal VLANs: none
Administrative private-vlan trunk associations: none
Administrative private-vlan trunk mappings: none
Operational private-vlan: none
Trunking VLANs Enabled: 1,10,20
Pruning VLANs Enabled: 2-1001
Capture Mode Disabled
Capture VLANs Allowed: ALL

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Don Johnston

1) It would be helpful to see the configs for these ports. Could be a speed mismatch.
2) Is this a "known good" cable? If not, either verify the cable or try a different cable.
3) Have you tried a straight-through cable? If not, try that.

LB1234

ASKER

TestSwitch# sh run
interface FastEthernet0/1
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 1,10,20
 switchport mode trunk

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48_port_switch# sh run
interface FastEthernet0/1
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 1,10,20
 switchport mode trunk
 switchport port-security

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2) both done
3) yes, tried straight thru

Don Johnston

Please post the output (for the 48_port_switch) of a "show port-security interface fastethernet 0/1"

LB1234

ASKER

48_port_switch#sh port-security interface fastEthernet 0/1
Port Security              : Enabled
Port Status                : Secure-shutdown
Violation Mode             : Shutdown
Aging Time                 : 0 mins
Aging Type                 : Absolute
SecureStatic Address Aging : Disabled
Maximum MAC Addresses      : 1
Total MAC Addresses        : 0
Configured MAC Addresses   : 0
Sticky MAC Addresses       : 0
Last Source Address:Vlan   : 000d.bdd1.3800:1
Security Violation Count   : 1

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Don Johnston

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LB1234

ASKER

That worked! Thanks! Question. Why did you include "shut" in there? Wasn't it already shut down? And why was turning off port-security necessary?

Don Johnston

Wasn't it already shut down?

Kind of. Usually when a port is in a secure violation, it's in what's known as errdisable state. Had you done a "show switchport status", it would have shown that.

To clear the condition, you can do a shut/no shut. But with port security enabled with only a single address being allowed, it would have just gone into a violation again.

As for turning off port security, I made an assumption that was not wanted. Especially since it had a one MAC address limit and it was configured on a trunk port. If you're only going to be allowing a single MAC address, it's pretty unlikely that you would need a trunk.