Leveraging IP Multicast to handle the BUM traffic allows a single packet to be sent to the Multicast group associated to the VNI. These BUM packets are sent to that group and then sent to every VTEP that has joined that multicast group. This will include ARP requests.
N9K-2
feature vn-segment-vlan-based
feature nv overlay
!
vlan 10
name VLAN10
vn-segment 10010
!
vlan 20
vlan 20
vn-segment 20020
!
interface nve1
no shutdown
source-interface loopback0
member vni 10010
mcast-group 224.0.1.10
member vni 20020
mcast-group 224.0.1.20
!
interface Ethernet1/5
switchport mode trunk
!
interface Ethernet1/2
switchport access vlan 10
spanning-tree port type edge
interface Ethernet1/3
switchport access vlan 20
spanning-tree port type edge
N9K-3
feature vn-segment-vlan-based
feature nv overlay
vlan 10
name VLAN10
vn-segment 10010
!
vlan 20
vlan 20
vn-segment 10020
!
interface nve1
no shutdown
source-interface loopback0
member vni 10010
mcast-group 224.0.1.10
member vni 10020
mcast-group 224.0.1.20
!
interface Ethernet1/2
switchport access vlan 10
spanning-tree port type edge
interface Ethernet1/3
switchport access vlan 20
spanning-tree port type edge
N9K-2# show ip mroute
IP Multicast Routing Table for VRF "default"
(*, 224.0.1.10/32), uptime: 00:04:47, nve ip pim
Incoming interface: Ethernet1/1, RPF nbr: 10.1.2.1
Outgoing interface list: (count: 1)
nve1, uptime: 00:04:47, nve
(10.0.0.2/32, 224.0.1.10/32), uptime: 00:04:47, nve mrib ip pim
Incoming interface: loopback0, RPF nbr: 10.0.0.2
Outgoing interface list: (count: 1)
Ethernet1/1, uptime: 00:04:47, pim
(*, 224.0.1.20/32), uptime: 00:04:36, nve pim ip
Incoming interface: Ethernet1/1, RPF nbr: 10.1.2.1
Outgoing interface list: (count: 1)
nve1, uptime: 00:04:36, nve
(10.0.0.2/32, 224.0.1.20/32), uptime: 00:04:36, nve mrib pim ip
Incoming interface: loopback0, RPF nbr: 10.0.0.2
Outgoing interface list: (count: 1)
Ethernet1/1, uptime: 00:03:46, pim
(*, 232.0.0.0/8), uptime: 00:11:03, pim ip
Incoming interface: Null, RPF nbr: 0.0.0.0
Outgoing interface list: (count: 0)
N9K-3# show ip mroute
IP Multicast Routing Table for VRF "default"
(*, 224.0.1.10/32), uptime: 00:04:23, nve ip pim
Incoming interface: Ethernet1/1, RPF nbr: 10.1.3.1
Outgoing interface list: (count: 1)
nve1, uptime: 00:04:23, nve
(10.0.0.3/32, 224.0.1.10/32), uptime: 00:04:23, nve mrib ip pim
Incoming interface: loopback0, RPF nbr: 10.0.0.3
Outgoing interface list: (count: 1)
Ethernet1/1, uptime: 00:03:47, pim
(*, 224.0.1.20/32), uptime: 00:04:18, nve ip pim
Incoming interface: Ethernet1/1, RPF nbr: 10.1.3.1
Outgoing interface list: (count: 1)
nve1, uptime: 00:04:18, nve
(10.0.0.3/32, 224.0.1.20/32), uptime: 00:04:18, nve mrib ip pim
Incoming interface: loopback0, RPF nbr: 10.0.0.3
Outgoing interface list: (count: 1)
Ethernet1/1, uptime: 00:03:46, pim
(*, 232.0.0.0/8), uptime: 00:11:05, pim ip
Incoming interface: Null, RPF nbr: 0.0.0.0
Outgoing interface list: (count: 0)
VPCS> ping 10.1.10.7
84 bytes from 10.1.10.7 icmp_seq=1 ttl=64 time=27.027 ms
84 bytes from 10.1.10.7 icmp_seq=2 ttl=64 time=27.472 ms
84 bytes from 10.1.10.7 icmp_seq=3 ttl=64 time=28.258 ms
84 bytes from 10.1.10.7 icmp_seq=4 ttl=64 time=27.453 ms
84 bytes from 10.1.10.7 icmp_seq=5 ttl=64 time=26.353 ms
VPCS> ping 10.1.20.8
84 bytes from 10.1.20.8 icmp_seq=1 ttl=64 time=31.223 ms
84 bytes from 10.1.20.8 icmp_seq=2 ttl=64 time=27.656 ms
84 bytes from 10.1.20.8 icmp_seq=3 ttl=64 time=34.899 ms
84 bytes from 10.1.20.8 icmp_seq=4 ttl=64 time=26.695 ms
84 bytes from 10.1.20.8 icmp_seq=5 ttl=64 time=24.362 ms
N9K-2# show mac address-table dynamic
Legend:
* - primary entry, G - Gateway MAC, (R) - Routed MAC, O - Overlay MAC
age - seconds since last seen,+ - primary entry using vPC Peer-Link,
(T) - True, (F) - False, C - ControlPlane MAC, ~ - vsan
VLAN MAC Address Type age Secure NTFY Ports
---------+-----------------+--------+---------+------+----+------------------
* 10 0050.7966.6804 dynamic 0 F F Eth1/2
* 10 0050.7966.6807 dynamic 0 F F nve1(10.0.0.3)
* 20 0050.7966.6808 dynamic 0 F F nve1(10.0.0.3)
N9K-3# show mac address-table dynamic
Legend:
* - primary entry, G - Gateway MAC, (R) - Routed MAC, O - Overlay MAC
age - seconds since last seen,+ - primary entry using vPC Peer-Link,
(T) - True, (F) - False, C - ControlPlane MAC, ~ - vsan
VLAN MAC Address Type age Secure NTFY Ports
---------+-----------------+--------+---------+------+----+------------------
* 10 0050.7966.6804 dynamic 0 F F nve1(10.0.0.2)
* 10 0050.7966.6807 dynamic 0 F F Eth1/2
* 20 0050.7966.6805 dynamic 0 F F nve1(10.0.0.2)
* 20 0050.7966.6808 dynamic 0 F F Eth1/3
N9K-2
feature vn-segment-vlan-based
feature nv overlay
!
vlan 10
name VLAN10
vn-segment 10010
!
vlan 20
vlan 20
vn-segment 20020
!
interface nve1
no shutdown
source-interface loopback0
member vni 10010
mcast-group 224.0.1.10
member vni 20020
mcast-group 224.0.1.20
!
interface Ethernet1/5
switchport mode trunk
!
interface Ethernet1/2
switchport access vlan 10
spanning-tree port type edge
interface Ethernet1/3
switchport access vlan 20
spanning-tree port type edge
N9K-3
feature vn-segment-vlan-based
feature nv overlay
vlan 10
name VLAN10
vn-segment 10010
!
vlan 20
vlan 20
vn-segment 10020
!
interface nve1
no shutdown
source-interface loopback0
member vni 10010
mcast-group 224.0.1.10
member vni 10020
mcast-group 224.0.1.20
!
interface Ethernet1/2
switchport access vlan 10
spanning-tree port type edge
interface Ethernet1/3
switchport access vlan 20
spanning-tree port type edge
N9K-2# show ip mroute
IP Multicast Routing Table for VRF "default"
(*, 224.0.1.10/32), uptime: 00:04:47, nve ip pim
Incoming interface: Ethernet1/1, RPF nbr: 10.1.2.1
Outgoing interface list: (count: 1)
nve1, uptime: 00:04:47, nve
(10.0.0.2/32, 224.0.1.10/32), uptime: 00:04:47, nve mrib ip pim
Incoming interface: loopback0, RPF nbr: 10.0.0.2
Outgoing interface list: (count: 1)
Ethernet1/1, uptime: 00:04:47, pim
(*, 224.0.1.20/32), uptime: 00:04:36, nve pim ip
Incoming interface: Ethernet1/1, RPF nbr: 10.1.2.1
Outgoing interface list: (count: 1)
nve1, uptime: 00:04:36, nve
(10.0.0.2/32, 224.0.1.20/32), uptime: 00:04:36, nve mrib pim ip
Incoming interface: loopback0, RPF nbr: 10.0.0.2
Outgoing interface list: (count: 1)
Ethernet1/1, uptime: 00:03:46, pim
(*, 232.0.0.0/8), uptime: 00:11:03, pim ip
Incoming interface: Null, RPF nbr: 0.0.0.0
Outgoing interface list: (count: 0)
N9K-3# show ip mroute
IP Multicast Routing Table for VRF "default"
(*, 224.0.1.10/32), uptime: 00:04:23, nve ip pim
Incoming interface: Ethernet1/1, RPF nbr: 10.1.3.1
Outgoing interface list: (count: 1)
nve1, uptime: 00:04:23, nve
(10.0.0.3/32, 224.0.1.10/32), uptime: 00:04:23, nve mrib ip pim
Incoming interface: loopback0, RPF nbr: 10.0.0.3
Outgoing interface list: (count: 1)
Ethernet1/1, uptime: 00:03:47, pim
(*, 224.0.1.20/32), uptime: 00:04:18, nve ip pim
Incoming interface: Ethernet1/1, RPF nbr: 10.1.3.1
Outgoing interface list: (count: 1)
nve1, uptime: 00:04:18, nve
(10.0.0.3/32, 224.0.1.20/32), uptime: 00:04:18, nve mrib ip pim
Incoming interface: loopback0, RPF nbr: 10.0.0.3
Outgoing interface list: (count: 1)
Ethernet1/1, uptime: 00:03:46, pim
(*, 232.0.0.0/8), uptime: 00:11:05, pim ip
Incoming interface: Null, RPF nbr: 0.0.0.0
Outgoing interface list: (count: 0)
VPCS> ping 10.1.10.7
84 bytes from 10.1.10.7 icmp_seq=1 ttl=64 time=27.027 ms
84 bytes from 10.1.10.7 icmp_seq=2 ttl=64 time=27.472 ms
84 bytes from 10.1.10.7 icmp_seq=3 ttl=64 time=28.258 ms
84 bytes from 10.1.10.7 icmp_seq=4 ttl=64 time=27.453 ms
84 bytes from 10.1.10.7 icmp_seq=5 ttl=64 time=26.353 ms
VPCS> ping 10.1.20.8
84 bytes from 10.1.20.8 icmp_seq=1 ttl=64 time=31.223 ms
84 bytes from 10.1.20.8 icmp_seq=2 ttl=64 time=27.656 ms
84 bytes from 10.1.20.8 icmp_seq=3 ttl=64 time=34.899 ms
84 bytes from 10.1.20.8 icmp_seq=4 ttl=64 time=26.695 ms
84 bytes from 10.1.20.8 icmp_seq=5 ttl=64 time=24.362 ms
N9K-2# show mac address-table dynamic
Legend:
* - primary entry, G - Gateway MAC, (R) - Routed MAC, O - Overlay MAC
age - seconds since last seen,+ - primary entry using vPC Peer-Link,
(T) - True, (F) - False, C - ControlPlane MAC, ~ - vsan
VLAN MAC Address Type age Secure NTFY Ports
---------+-----------------+--------+---------+------+----+------------------
* 10 0050.7966.6804 dynamic 0 F F Eth1/2
* 10 0050.7966.6807 dynamic 0 F F nve1(10.0.0.3)
* 20 0050.7966.6808 dynamic 0 F F nve1(10.0.0.3)
N9K-3# show mac address-table dynamic
Legend:
* - primary entry, G - Gateway MAC, (R) - Routed MAC, O - Overlay MAC
age - seconds since last seen,+ - primary entry using vPC Peer-Link,
(T) - True, (F) - False, C - ControlPlane MAC, ~ - vsan
VLAN MAC Address Type age Secure NTFY Ports
---------+-----------------+--------+---------+------+----+------------------
* 10 0050.7966.6804 dynamic 0 F F nve1(10.0.0.2)
* 10 0050.7966.6807 dynamic 0 F F Eth1/2
* 20 0050.7966.6805 dynamic 0 F F nve1(10.0.0.2)
* 20 0050.7966.6808 dynamic 0 F F Eth1/3
