Change configuration on Catalyst 3560

Unanswered Question
Mar 24th, 2010
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I have an a switch 3560 with IOS c3560-ipbase-mz.122-35 where from port fa 0/1 until port fa 0/22 thera are connected

22 AP Cisco 1242.

On this ports I have configured only "switchport access vlan 3", which is vlan for wi-fi.

Yesterday, for each of this ports I have found:

switchport nonegotiate

switchport mode trunk

switchport trunk encapsulation dot1q

mls qos trust cos

auto qos voip trust

spanning-tree bpduguard enable

and was impossible reach AP and my guest could not surf on Internet.

What can be happen ?

Why did switch change configuration ?

Best regards


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Giuseppe Larosa Thu, 03/25/2010 - 11:04
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Hello Lorenzo,

have you deployed autoQoS recently?

but I would not expect a change of switchport mode.

one possibility is: someone applied a wrong interface range in an attempt to configure some ports as trunk that included these ports

if the device is under TACACS+ you can check the commands applied to the switch to verify if commands have been added in some way.

Hope to help


lformelli Thu, 03/25/2010 - 11:39
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Thank you Giuseppe

with your answer I have understood

that's impossible to change configurations itself.

best regards



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