HPE FlexFabric 5940 Series Configuration Manual page 42

Intra-VXLAN traffic forwarding between sites
As shown in
sites (for example, from VM 1 to VM 4 in VXLAN 10):
1. VM 1 sends an ARP request to obtain the MAC address of VM 4.
2. GW 1 performs the following operations:
a. Creates an ARP entry for VM 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. VM 1 creates an ARP entry for VM 4. The MAC address in the entry is the MAC address of
VSI-interface 10 on GW 1.
4. GW 2 (the VTEP for VM 4) performs the following operations:
a. De-encapsulates the ARP request and creates an ARP entry for VM 1. The entry contains
VM 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. VM 4 creates an ARP entry for VM 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 VM 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 VM 4. The entry contains
VM 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 VM 1 and VM 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
(for example, from VM 1 in VXLAN 10 to VM 5 in VXLAN 20):
1. VM 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 VM 1 and replies with the MAC address of VSI-interface 10 (the
gateway interface for VXLAN 10).
3. VM 1 sends the packet destined for VM 5 to GW 1.
4. GW 1 sends an ARP request to the local site and remote sites to obtain the MAC address of VM
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 VM 1. The entry contains
VM 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. VM 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 VM 5.
Figure 16, the network uses the following process to forward traffic in a VXLAN between
Figure 16, the network uses the following process to forward traffic between VXLANs
38