About Virtual Extensible LAN (VXLAN) Tunnels

VXLAN is a simple tunneling mechanism that allows overlaying a Layer 2 (L2) network over a Layer 3 (L3) underlay with the use of any IP routing protocol. It uses MAC Address-in-User Datagram Protocol (MAC-in-UDP) encapsulation. A remote device, such as the Gigamon cloud, GigaVUE TA Series, GigaVUE H Series, or a customer-specific device, encapsulates the filtered traffic, adds an encapsulation header that consists of Layer 2 + IP + UDP + VXLAN headers. The encapsulated packet is sent out of the circuit port, which is connected to the public network (the Internet). This packet is routed in the public network to reach the main office site. The packet is ingressed at the circuit port configured in the GigaVUE-H Series or GigaVUE-TA Series device at the main office. After validation of the source port, destination port, and VXLAN Network Identifier (VNI) of the packet, the VXLAN tunnel header will be removed and the inner payload will be sent to the tools based on the map rules configured.

The following figure illustrates the VXLAN tunnel encapsulation and decapsulation.

Figure 32 VXLAN Tunnel Encapsulation and Decapsulation

In this diagram, traffic is tapped on a GigaVUE-TA200 device at a remote site, and then it is tunneled through VXLAN encapsulation across the network before it reaches the GigaVUE-HC3 device at the main office site, which is connected to the actual tools. The tunnel decapsulation is executed on an ingress circuit port (IP interface). After tunnel decapsulation, the packet is presented to the flow mapping module to filter based on map rule parameters.

Refer to the following sections for details about VXLAN tunnels:

VXLAN Tunnel Configuration—Rules and Notes
Configure VXLAN Tunnel to Encapsulate Traffic
Configure VXLAN Tunnel to Decapsulate Traffic

 

 

VXLAN Tunnel Configuration—Rules and Notes

Keep in mind the following rules and notes when working with VXLAN tunnels:

VXLAN tunnels are supported only on GigaVUE‑HC1, GigaVUE-HC2 CCv2, GigaVUE-HC3, GigaVUE-TA40, GigaVUE-TA100, GigaVUE-TA200 devices and GigaVUE-TA25.
A maximum of 1500 VXLAN IDs are supported.
Flow mapping that is configured on the circuit port used for VXLAN decapsulation will filter only the inner packet attributes along with VXLAN-ID. Any other non-tunneled packets that ingress on this circuit port will not be filtered or redirected to tool ports, even if it matches the rules configured on the map.
IPv6 protocol is not supported with VXLAN tunnels.
Ingress VLAN tagging and Tool Mirror features are not supported with VXLAN tunnels.
Any encapsulated packet that exceeds the MTU value configured for the IP interface will be discarded because IP fragmentation and reassembly of packets are not supported.
VXLAN tunnel encapsulation is not supported on circuit GigaStreams.
VXLAN tunnel decapsulation is supported only on encapsulated packets that are not tagged.
Map-passall is not supported for the circuit port that encapsulates or decapsulates the VXLAN packet.
When a circuit port is configured for VXLAN tunnel decapsulation, you cannot use the port in any other regular map in which a network port is configured as the source port.
Inner VLAN qualifier is not supported on the port in which the VXLAN tunnel decapsulation is enabled.
VXLAN ID qualifier is available as part of existing static templates. Following table provides details about the platforms for which the static templates are available:

 

Template

Platform

GigaVUE-HC2 (CCv2)/GigaVUE‑HC1/GigaVUE-TA40

GigaVUE-HC3/GigaVUE-TA100

IPv4

No

Yes

IPv6

Yes

Yes

IPv4+UDA

No

Yes

IPv4+MAC

Yes

Yes

UDA

Yes

Yes