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Switch/Router VLAN configuration problems


I've recently purchased a Cisco catalyst 2960S-24TS-L & setup 3 VLANS 10 (no current IP),20 ( and 30 ( to reflect the router VLAN configuration & ip information. When conntecing my PC to the switch to test connectivity on (2.1 & 3.1) I'm unable to connect to the the net but can sucessfully ping GW (int FE0.20 & FE0.30) & 3.1.

The router is an Cisco 1801 & it seems this is where the confuration issue is but I'm unable to figure out how to complete the setup. It has been quite awhile since I've configured a Cisco router & would appreciate any help.

Ive never had this router connected to a switch so all router switch ports are in the default VLAN1 (, with FE0  disabled. In trying to get the switch to communicate with the router I made the following router config modifcations.

FE0 enabled with subinterfaces configured

FE0.10-currently no ip



I have two issues I want to resolve:

1) I do not know what additional steps are required to allow 2.1.& 3.1 VLANs to access the net.

2) I want to disbale VLAN1 if possible & use the network IP for VLAN10 ( I'm unsure how to do this as any change on VLAN1 immediately breaks router access and the router reconfiguration becomes more complicated with chages to the FW ACL etc.

Any help with explicit detailed directions(including commands) to complete issues 1 & 2 would be very appreciated.

Thanks in advance.



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Switch/Router VLAN configuration problems

Hello Mike,

if Mars is the hostname of the switch we can see that no L2 port is associated to the new Vlans 10,20,30

Mars#sh vlan-switch

VLAN Name                             Status    Ports

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

1    default                          active    Fa1, Fa2, Fa3, Fa4, Fa5, Fa6

                                                Fa7, Fa8

10   General                          active    >>>> empty port list

20   SAN                              active    >>>> empty port list

30   Management                       active    >>>> empty port list

as a result of this the corresponding L3 interfaces are in up/down state ( show interface vlan output )

The port that you connect to the router fas0 interface has to be configured as a L2 trunk that carries vlan 10,20,30

int fasx


! following command may not be present in your switch

switchport trunk encapsulation dot1q

! if not present is not needed

switchport mode trunk

switchport trunk allowed vlan 10,20,30

the port where you connect the PC for tests has to be associated to the corresponding vlan using

int fas y


switchport mode access

switchport access vlan XX

in this way you can also remove vlan1 from all ports on the switch

Hope to help


Switch/Router VLAN configuration problems

If i can add a comment to Giuseppe's explanation, you should sutdown Vlan 1 too and doing some final verification on the switchport status and STP status of your network.


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