Guys, In my scenario which is deployed with maas and juju, I have a network 10.10.10.0/24 which is used to deploy openstack base churm bundle.
Also the maas and juju are within this network/subnet.
Recently I have added a new compute node to the cluster from a different network segment , 10.10.13.10/24
3 nova computes are in the same network segment but the newly added is from a different subnet.
External network uses flat type and my instances which are created in the new compute node are not accessible via floating/Fixed IP from 10.10.10.0/24 subnet.
If your external network is flat, then new nodes attached to 10.10.13.0/24 will bridge external to 10.10.13.0/24
Addresses from 10.10.10.0/24 are obviously not reachable via 10.10.13.0/24.
I would consider using tagged VLAN for your external network, so no matter which native VLAN your nova nodes are attached to external networking will work
10.10.10.0/24 and 10.10.13.0/24 may be reachable from each other because they’re routed.
Think about it this way:
Flat network is like plugging a cable into an unmanaged switch.
In your example you have two switches
Switch A : 10.10.10.0/24
Switch B : 10.10.13.0/24
If you plug a cable into Switch A, and assign your interface an IP of 10.10.10.100 networking will work because the gateway (10.10.10.1) will be reachable because you’re in the same network.
If you use Switch A again but assign an IP of 10.10.13.100, the gateway (10.10.10.1) for that switch is unreachable because your interface is sitting in the wrong network.
You’re at school, but the reason you can’t hear anyone is because you’re in the wrong lecture hall.
With VLANs, technically you only need one switch. To drop yourself into a different network all you need to do is add a VLAN tag to your network packet.
You’re still at school, but you’re not bound to a lecture hall. You have the ability to drop into any lesson by putting on marked headphones.
Headphone 1 (VLAN 1 ) puts you in Psychology class (10.10.10.0/24)
Headphone 2 (VLAN 2) puts you in Science class (10.10.13.0/24)
So if half your nova nodes are in lecture hall 1 and the other half are outside on the track; by using the headphones (VLANs) they can all listen to the psychology lesson (10.10.10.0/24) irrespective where they’re physical located ( or plugged in )
Thank you for clearing this , I need to know I have to buy a managed switch or this whole process can be done with MAAS or OpenVswitch , as I can see there is a section in maas that can put tags on specific vlan.
If it works with maas, would you please guide me if there is
You don’t actually configure the VLAN for external connectivity for Openstack in MaaS. You do it in Openstack.
The physical switch does need to be configured with the VLAN.
OVS will then add the tag on the external network.
