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need help setting up a cisco switch

techdrive asked
Please excuse me as I know this might be a really basic question but could sure use some assistance. I have 4 subnets setup on my router and trying to connect them to my 3 switches. I have the following cisco switches.they are connected to a soho gigabit switch and that goes to a cisco 1841 router. I am doing router on a stick/intervlan

1) 3560 uplink port 15
2) 2960 uplink port 15
3) 3750 uplink port 23

I was able to setup vlan1 and mapped an ip to this port on the 2960 switch. When I tried to setup the other vlans and map them to ip addresses they are down and even with no shutdown cannot get the protocol to come up. Do I need to have this mapped to an uplink for every vlan I have.,

Interface              IP-Address      OK? Method Status                Protocol
Vlan1             YES manual up                    up
Vlan20           YES manual up                    down
Vlan96           YES manual up                    down

My end goal is to get these vlans setup and working on the others

FastEthernet0              unassigned      YES manual up                    up  
FastEthernet0.32     YES manual up                    up  
FastEthernet0.96     YES manual up                    up  
FastEthernet0.128   YES manual up                    up  
FastEthernet0.160   YES manual up                    up  
FastEthernet1         YES manual up                    up
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I also went on the switch and verified that my switch was setup on port 15 as trunking. My assumption was that all the vlans would be routed over that interface.
Network Security Engineer
Distinguished Expert 2018
If you have a router on stick this is what you need to do:

Router side:

Configure the fa0/0 with sub interface as you know.
Ip address
ip nat inside

Ip address

Switch side:

Configure one the cisco switch port as a trunk allowing all the vlans 1,20,99
switchport trunk encapsulation dot1q
switchport mode trunk

After that add on the switch vlan 20,96.
once you have done that add those vlan to their respective ports.

Let me know if that helps.


Crossing my fingers

Switch#sh interfaces fastEthernet0/15 trunk

Port        Mode         Encapsulation  Status        Native vlan
Fa0/15      on           802.1q         trunking      1

Port      Vlans allowed on trunk
Fa0/15      1-4094

Port        Vlans allowed and active in management domain
Fa0/15      1,20,96

Port        Vlans in spanning tree forwarding state and not pruned
Fa0/15      1,20,96


Sweet the interfaces are up now.
Hemil AquinoNetwork Security Engineer
Distinguished Expert 2018

If the interface are up you're good to go.
Hemil AquinoNetwork Security Engineer
Distinguished Expert 2018

I bet you forgot the command encapsulation 802.1q for trunking xD