Modular Layer 2 (ML2) Neutron plug-in allows OpenStack networking to simultaneously utilize multiple layer 2 networking technologies such as 802.1Q and VXLAN for virtual instances.
External networks are managed using Mechanism Drivers. The Mechanism Driver is responsible for taking the information established by the Type Driver and ensuring that it is properly applied given the specific networking mechanisms that are enabled. A single OpenStack installation can use multiple ML2 Mechanism Drivers.
Extreme ML2 Mechanism driver within Neutron initiates Neutron API calls for network management. OpenStack Service in EFA translates the Neutron network management calls to appropriate tenant API calls and provisions the fabric with appropriate L2 networking constructs.
The following figure shows an overview of the ML2 Mechanism Driver within Neutron.
The following table shows an example mapping of the OpenStack Networks to the Tenant Service EPG constructs.
VM | Neutron Network | Tenant Service (EPG) |
---|---|---|
VM1 | GREEN_NETWORK (VLAN30) UUID =74cbf489-f3d9-41c7-bbb2-6cb7df33da6d | 74cbf489-f3d9-41c7-bbb2-6cb7df33da6d
|
VM2 | GREEN_NETWORK (VLAN30) UUID =74cbf489-f3d9-41c7-bbb2-6cb7df33da6d | |
Naming convention for EPG creation is <Neutron Network UUID>. |
EPG provisioning on the fabric creates a L2 network on the fabric spanning VM1 and VM2 with necessary fabric mappings. This creates the necessary constructs to establish an end-to-end connectivity between DB1 and DB2.
The following table shows an example of the configuration on the leaf nodes.
EPG | Switch Configuration | Comments |
---|---|---|
74cbf489-f3d9-41c7-bbb2-6cb7df33da6d (GREEN_NETWORK)
|
vlan 30 description L2 Tenant vlan ! evpn default vlan add 30 ! |
VLAN 30 configured on Leaf-1 and Leaf-4 VLAN 30 added to evpn Note: VLAN to VNI mapping
is set to auto as part of fabric setup.
|
interface ethernet 0/1 switchport switchport trunk allowed vlan add 30 no shutdown ! |
Interface configurations on both the switches, Leaf-1 and Leaf-4. |