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tenant and external network vlan mapping

asked 2015-04-30 19:37:31 -0500

beinghuman gravatar image

updated 2015-04-30 19:42:00 -0500

Hi Everyone,

I have deployed openstack Juno on VMware with 3 nodes one for each network, controller & compute following the below link using VLAN network.

In the neutron confuration i am using VLAN's for both tenant and external network. I have got my tenant network working and they are able to ping each other but after i allocate floating IP address to the instance i cant ping external network. I can see some of the issues such as tenant network and external network are not in the same VLAN but i dont know if that is a requirement. Below are additional details of my setup,

Tenant network(eth1) - VLAN 1(This link is a trunk link connecting compute node to network node to access external network)

External network(eth2) - VLAN 4(This link is a trunk link connecting to physical switch and i have the same VLAN4 on the switch configured)

I am confused as to whether external & tenant network VLAN numbers should be same or not? I tried giving same number for both but it didnt work which makes sense as we cant have same VLAN number in the network. If it cant be the same then how do i map the VLAN traffic from tenant network to external network on the trunk link so i can reach internet? I have tried referring to many guides but couldnt find any clarity on how to map tenant traffic to external traffic when using VLAN type for tenant network. I hope i was able to explain correctly. Can someone please help me here as i need to soon deploy this in prod env? Any help would be much appreciated.

I have also attached my network config for reference.

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C:\fakepath\Openstack Junu config-page-006.jpg

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answered 2015-04-30 20:03:55 -0500

SamYaple gravatar image

Different networks will have different vlans.

With vlans, you have two options with your tenant networks.

  1. Use a neutron l3 router. Attach a port to your tenant network and set the gateway to your external network
  2. Outside of openstack, assign a gateway ip address to an interface in the same vlan as the tenant network (do not use neutron l3 routers)

Option 1 is the "Openstack" way to do this.

However Option 2 is a good option if you have the proper equipment and know what you are doing. You won't be able to use "floating ips" through Openstack in that case though. You can still provide that functionality outside of Openstack on an upstream network device.

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I'm using opt 1. Does the tenant & ext net VLAN need to be same? Juno doesnt allow me to create same VLAN for tenant and ext net so how can i reach via trunk link to the instance if the VLAN numbers are not same. How can i use ext trunk to map multiple ext VLAN subnets to multiple tenant VLANs? thks

beinghuman gravatar imagebeinghuman ( 2015-04-30 21:11:10 -0500 )edit

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Asked: 2015-04-30 19:37:31 -0500

Seen: 1,281 times

Last updated: Apr 30 '15