Hi Mike,

With those requirements, I think dual-homing the instances may be the best 
approach.


In my mind, you would have 5 networks:


A - External Network 1

B - External Network 2

C - Tenant Network 1

D - Tenant Network 2

E - Shared Tenant Network (No gateway)


Because routers can only connect to one external network at a time, and a 
tenant network can only be connected to one router at a time, you would need 
two routers:


Router 1

Router 2


You would connect them as follows:


External Network 1 <-> Router 1 <-> Tenant Network 1

External Network 2 <-> Router 2 <-> Tenant Network 2


The VMs would then connect as follows:


Tenant Network 1 <-> VM1 <-> Shared Network

Tenant Network 2 <-> VM2 <-> Shared Network


With no gateway set on the shared network, you won't have to worry about 
multiple default routes, nor do you need to worry about terminating that 
network off a router. It's simply isolated.


Hope that helps,

James

________________________________
From: Mike Spreitzer <mspre...@us.ibm.com>
Sent: Wednesday, April 8, 2015 12:28 PM
To: openstack
Subject: [Openstack] [neutron] how to use multiple external networks?

Supposing there are two external provider networks, and a tenant wants (a) some 
of his Compute Instances to have floating IP addresses on one of those external 
networks, (b) some other of his Compute Instances to have floating IP addresses 
on the other external network, and (c) all of his Compute Instances to be able 
to talk to each other using only tenant private networking, what arrangement of 
tenant networks and routers would accomplish this?  In Juno, if it matters.

Thanks,
Mike

_______________________________________________
Mailing list: http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack
Post to     : openstack@lists.openstack.org
Unsubscribe : http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack

Reply via email to