API Guide

Bridge domain A L2 domain that receives packets from member interfaces and forwards or floods them to other member
interfaces based on the destination MAC address of the packet. OS10 supports two types of bridge
domains: simple VLAN and virtual network.
● Simple VLAN: A bridge domain a VLAN ID represents. Traffic on all member ports is assigned with the
same VLAN ID.
● Virtual network: A bridge domain a virtual network ID (VNID) represents. A virtual network supports
overlay encapsulation and maps with either a single VLAN ID in a switch-scoped VLAN or with multiple
(Port,VLAN) pairs in a port-scoped VLAN.
Distributed
routing
All VTEPs in a virtual network perform intersubnet routing and serve as L3 gateways in two possible
modes:
● Asymmetric routing: All VTEPs can perform routing. Routing decisions are made only on ingress
VTEPs. Egress VTEPs perform bridging.
● Symmetric routing: All VTEPs perform routing. Routing decisions are made on both ingress and egress
VTEPs.
Virtual network In OS10, each L2 flooding domain in the overlay network is represented as a virtual network.
Virtual network
identifier (VNID)
A 16-bit ID number that identifies a virtual network in OS10.
Virtual-network
interface
A router interface that connects a virtual network bridge to a tenant VRF routing instance.
Access port A port on a VTEP switch that connects to an end host and is part of the overlay network.
Network port A port on a VTEP switch that connects to the underlay network.
Switch-scoped
VLAN
A VLAN that is mapped to a virtual network ID (VNID) in OS10. All member ports of the VLAN are
automatically added to the virtual network.
● You can map only one VLAN ID to a virtual network.
● Ideally suited for existing tenant VLANs that stretch over an IP fabric using VXLAN.
Port-scoped
VLAN
A Port,VLAN pair that maps to a virtual network ID (VNID) in OS10. Assign an individual member interface
to a virtual network either with an associated tagged VLAN or as an untagged member. Using a port-
scoped VLAN, you can configure:
● The same VLAN ID on different access interfaces to different virtual networks.
● Different VLAN IDs on different access interfaces to the same virtual network.
VXLAN as NVO solution
Network virtualization overlay (NVO) is a solution that addresses the requirements of a multi-tenant data center, especially one
with virtualized hosts. An NVO network is an overlay network that is used to extend L2 connectivity among VMs belonging to a
tenant segment over an underlay IP network. Each tenant payload is encapsulated in an IP packet at the originating VTEP. To
access the payload, the tenant payload is stripped of the encapsulation at the destination VTEP. Each tenant segment is also
known as a virtual-network and is uniquely identified in OS10 using a virtual network ID (VNID).
VXLAN is a type of encapsulation used as an NVO solution. VXLAN encapsulates a tenant payload into IP UDP packets for
transport across the IP underlay network. In OS10, each virtual network is assigned a 24-bit number that is called a VXLAN
network identifier (VNI) that the VXLAN-encapsulated packet carries. The VNI uniquely identifies the tenant segment on all
VTEPs. OS10 sets up ASIC tables to:
● Enables creation of a L2 bridge flooding domain across a L3 network.
● Facilitates packet forwarding between local ports and tunneling packets from the local device to a remote device.
Configure VXLAN
To extend a L2 tenant segment using VXLAN, follow these configuration steps on each VTEP switch:
1. Configure the source IP address used in encapsulated VXLAN packets.
2. Configure a virtual network and assign a VXLAN VNI.
3. Configure VLAN-tagged access ports.
VXLAN
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