Routing from vlans to external router

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As a follow up to my last post on inter-vlan routing, which is now working, both PCs on separate vlans cannot get to the internet. I tried 'configure iproute add default gateway and that did not work.

If the default gateway of the PC is the VLAN how does the VLAN know about the default GW of the router?

Thanks for the help.
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Kurt Hansen

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Posted 3 years ago

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Patrick Voss, Employee

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If the destination IP is not present in the routing table it should take the default route. Can you provide a small topology along with the VLANs and subnets we can take?
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Harkanwaljeet Singh

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As you said, that inter vlan routing is working, it means both the PCs placed in different vlans are able to talk to each other.

I do not know your network topology at this time, but I assume, you have another L3 connectivity between router and extreme device (on which two vlans are created and two PCs are connected) that's why you mentioned about adding default route.  Can you please check again if the default route has router's IP as the default gateway?

According to topology, you may need to add routes on router towards PC's subnets.

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Drew C., Community Manager

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Hi Kurt,
Take a look at my post in this thread (it's the "official one) - maybe you'll find my explanation there to be helpful in your setup.

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Kurt Hansen

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Here is layout. I know I can setup multiple vlans on router and manage there, but I don't want to have a lot of vlan interfaces on router just to allow a PC or two to talk with another PC in other vlan.

The real scenario is I have a management vlan and a POS vlan and one PC on the management vlan needs access to PC on POS vlan but no others need access, and both vlans need access to internet. 

VLAN tags are backwards in drawing....

# Module vlan configuration.#
configure vlan default delete ports all
configure vr VR-Default delete ports 1-24
configure vr VR-Default add ports 1-24
configure vlan default delete ports 10, 18
create vlan "v10"
configure vlan v10 tag 10
create vlan "v20"
configure vlan v20 tag 20
configure vlan Default add ports 1-9, 11-17, 19-24 untagged
configure vlan v10 add ports 18 untagged
configure vlan v20 add ports 10 untagged
configure vlan Default ipaddress
enable ipforwarding vlan Default
configure vlan v10 ipaddress
enable ipforwarding vlan v10
configure vlan v20 ipaddress
enable ipforwarding vlan v20

# Module fdb configuration.

# Module rtmgr configuration.
configure iproute add default
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Brandon Clay, Escalation Support Engineer

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Hi Kurt,

I would check on the router to make sure that there are routes for and pointing back to