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VLANs cannot communicate

alexgoston
Level 1
Level 1

Hello!
I have a project work for school. In the "Budapest Net" workstation there are 2 subnets (10.10.0.0/29, 10.10.0.16/28). The first one uses VLAN 20, the second one uses VLAN 10. I used ROAS routing, the VLANs can communicate inside one VLAN. But the 2 VLANs cannot reach each other. It looks like this: help.png
I know it is not a basic topology/network, but it should be like this to simulate the right thing. Now the question: does anybody know how the hell can I make the two VLANs reach each other?

1 Accepted Solution

Accepted Solutions

Martin L
VIP
VIP

simple changes if all PCs are in vlan 20 on right side is for right swtch link connected to router should not be trunk but only access port

interface GigabitEthernet0/1

switchport access vlan 20

switchport mode access

and for left switch side all devices are in vlan 10, same thing not a trunk but access one

interface GigabitEthernet0/1

switchport access vlan 10

switchport mode access

 

Edit: if u do planing have different vlans on left and right side, then u need convert router to be ROAS,

 

Regards, ML
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7 Replies 7

Martin L
VIP
VIP

attach your PT lab file here in a zip format

Regards, ML
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Here it is. 

Edit: if u do planing have different vlans on left and right side, then u need convert router to be ROAS,

ROAS config is

interface GigabitEthernet1/0

no ip address

!

interface GigabitEthernet1/0.10

encapsulation dot1Q 10

ip address 10.10.0.17 255.255.255.248

!

interface GigabitEthernet2/0

no ip address

!

interface GigabitEthernet2/0.20

encapsulation dot1Q 20

ip address 10.10.0.1 255.255.255.240

 

Regards, ML
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balaji.bandi
Hall of Fame
Hall of Fame

there is other post similar issue have a look my suggestions :

https://community.cisco.com/t5/online-tools-and-resources/help-with-default-gateway-on-router-interfaces/m-p/4943296#M1447

you need to post the configuration here for the community help

 

BB

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Martin L
VIP
VIP

simple changes if all PCs are in vlan 20 on right side is for right swtch link connected to router should not be trunk but only access port

interface GigabitEthernet0/1

switchport access vlan 20

switchport mode access

and for left switch side all devices are in vlan 10, same thing not a trunk but access one

interface GigabitEthernet0/1

switchport access vlan 10

switchport mode access

 

Edit: if u do planing have different vlans on left and right side, then u need convert router to be ROAS,

 

Regards, ML
**Please Rate All Helpful Responses **

Thank you, it worked.
On the switches all the ports are in access mode, except the ports that are connected between 2 switches. Between them it is configured as trunk. Now everything just works fine as they should.

and you also noticed my point regarding ROAS settings in case of 2 - which is the most use allover the networks

Regards, ML
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