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Intra-VXLAN traffic forwarding between sites
As shown in
, the network uses the following process to forward traffic in a VXLAN between
sites (for example, from Terminal 1 to Terminal 4 in VXLAN 10):
1.
Terminal 1 sends an ARP request to obtain the MAC address of Terminal 4.
2.
GW 1 performs the following operations:
a.
Creates an ARP entry for Terminal 1 and replies with the MAC address of VSI-interface 10
(the gateway interface for VXLAN 10).
b.
Replaces the sender MAC address of the ARP request with the MAC address of
VSI-interface 10, and then floods the request to all remote VTEPs.
3.
Terminal 1 creates an ARP entry for Terminal 4. The MAC address in the entry is the MAC
address of VSI-interface 10 on GW 1.
4.
GW 2 (the VTEP for Terminal 4) performs the following operations:
a.
De-encapsulates the ARP request and creates an ARP entry for Terminal 1. The entry
contains Terminal 1's IP address (10.1.1.11), the MAC address of VSI-interface 10 on GW 1,
and the incoming tunnel interface.
b.
Replaces the sender MAC address of the request with the MAC address of VSI-interface 10
on GW 2, and then floods the request to the local site in VXLAN 10.
5.
Terminal 4 creates an ARP entry for Terminal 1, and then sends a reply to GW 2. The MAC
address in the ARP entry is the MAC address of VSI-interface 10 on GW 2.
6.
GW 2 performs the following operations:
a.
Creates an ARP entry for Terminal 4.
b.
Replaces the sender MAC address of the request with the MAC address of VSI-interface 10
on GW 2, and sends the reply to GW 1.
7.
GW 1 de-encapsulates the ARP request and creates an ARP entry for Terminal 4. The entry
contains Terminal 4's IP address (10.1.1.12), the MAC address of VSI-interface 10 on GW 2,
and the incoming tunnel interface.
8.
For subsequent traffic between Terminal 1 and Terminal 4, GW 1 and GW 2 use their
respective ARP tables to make the forwarding decision.
Inter-VXLAN traffic forwarding between sites
As shown in
, the network uses the following process to forward traffic between VXLANs
(for example, from Terminal 1 in VXLAN 10 to Terminal 5 in VXLAN 20):
1.
Terminal 1 sends an ARP request to obtain the MAC address of the gateway at 10.1.1.1.
2.
GW 1 creates an ARP entry for Terminal 1 and replies with the MAC address of VSI-interface
10 (the gateway interface for VXLAN 10).
3.
Terminal 1 sends the packet destined for Terminal 5 to GW 1.
4.
GW 1 sends an ARP request to the local site and remote sites to obtain the MAC address of
Terminal 5. In the ARP request, the sender IP address is 20.1.1.1, and the sender MAC
address is the MAC address of VSI-interface 20 on GW 1.
5.
GW 2 performs the following operations:
a.
De-encapsulates the ARP request and creates an ARP entry for Terminal 1. The entry
contains Terminal 1's IP address (20.1.1.1), the MAC address of VSI-interface 20 on GW 1,
and the incoming tunnel interface.
b.
Replaces the sender MAC address of the request with the MAC address of VSI-interface 20
on GW 2, and then floods the request to the local site in VXLAN 20.
6.
Terminal 5 creates an ARP entry for GW 2, and then sends a reply to GW 2. The entry contains
the IP address (20.1.1.1) and MAC address of VSI-interface 20 on GW 2).
7.
GW 2 performs the following operations:
a.
Creates an ARP entry for Terminal 5.
