1. Description
- Same as the previous article “1 Experiment 1: Implementing Cisco VxLAN & centralized gateway based on static Ingress Replication”, implementing VxLAN based on Multicast also uses traffic-driven MAC address flooding learning and VTEP neighbor establishment. , there is no control level;
- Unlike implementing VxLAN based on Static Ingress Replication, implementing VxLAN based on Multicast does not require manual configuration of peers for each VNI;
- The tunnel between VTEPs will be automatically established when traffic is triggered, that is, data-driven;
- Different from using Static Ingress Replication to forward BUM (broadcast, unknown unicast, multicast) traffic, forwarding BUM traffic based on Multicast can effectively save the bandwidth of the VTEP uplink (see multicast network characteristics for details).
2. VxLAN experiment based on Multicast
2.1 Experimental environment
| Tools | Version | Remarks |
|---|---|---|
| EVE-NG | 2.0.3-105 | Emulator |
| Cisco Nexus 9000v | 7.0. 3.I7.8 | Switches that support VxLAN, N9K1, N9K-2, N9K-3 and N9K-4 in the topology |
| Wireshark | 3.2.2 | Packet capture software |
2.2 Experimental topology
image.png
- N9K1, N9K-2, N9K-3 and N9K-4 run the OSPF protocol;
- N9K1, N9K-2, N9K-3 and N9K-4 run PIM Sparse Mode, where the PIM RP is 1.1.1.1;
- Enable PC1, PC2 and PC3 to communicate with each other.
2.3 Experimental configuration
2.3.1 Configuring Underlay three-layer network
- The interconnection interface and loopback interface of the device are advertised into OSPF Area 0.
N9K-1 Configuration:
feature ospf router ospf n9k-1 router-id 1.1.1.1 interface Ethernet1/1 no switchport mtu 9216 IP address 10.1.1.1/30 ip ospf network point-to-point ip router ospf n9k-1 area 0.0.0.0 no shutdown interface Ethernet1/2 no switchport mtu 9216 IP address 10.1.1.5/30 ip ospf network point-to-point ip router ospf n9k-1 area 0.0.0.0 no shutdown interface Ethernet1/3 no switchport mtu 9216 IP address 10.1.1.9/30 ip ospf network point-to-point ip router ospf n9k-1 area 0.0.0.0 no shutdown interface loopback0 ip address 1.1.1.1/32 ip router ospf n9k-1 area 0.0.0.0
N9K-2 Configuration:
vlan 10 featureospf router ospf n9k-2 router-id 2.2.2.2 interface Ethernet1/1 no switchport mtu 9216 IP address 10.1.1.2/30 ip ospf network point-to-point ip router ospf n9k-2 area 0.0.0.0 no shutdown interface loopback0 IP address 2.2.2.2/32 ip router ospf n9k-2 area 0.0.0.0 interface Ethernet1/2 switchport access vlan 10 spanning-tree port type edge
N9K-3 Configuration:
vlan 10 featureospf router ospf n9k-3 router-id 3.3.3.3 interface Ethernet1/1 no switchport mtu 9216 IP address 10.1.1.6/30 ip ospf network point-to-point ip router ospf n9k-3 area 0.0.0.0 no shutdown interface loopback0 IP address 3.3.3.3/32 ip router ospf n9k-3 area 0.0.0.0 interface Ethernet1/2 switchport access vlan 10 spanning-tree port type edge
N9K-4 Configuration:
vlan 10 featureospf router ospf n9k-4 router-id 4.4.4.4 interface Ethernet1/1 no switchport mtu 9216 IP address 10.1.1.10/30 ip ospf network point-to-point ip router ospf n9k-4 area 0.0.0.0 no shutdown interface loopback0 IP address 4.4.4.4/32 ip router ospf n9k-4 area 0.0.0.0 interface Ethernet1/2 switchport access vlan 10 spanning-tree port type edge
Configuration verification:
View the N9K-1 OSPF routing table:
N9K-1# show ip route ospf
IP Route Table for VRF "default"
'*' denotes best ucast next-hop
'**' denotes best mcast next-hop
'[x/y]' denotes [preference/metric]
'%<string>' in via output denotes VRF <string>
2.2.2.2/32, ubest/mbest: 1/0
*via 10.1.1.2, Eth1/1, [110/41], 2d10h, ospf-n9k-1, intra
3.3.3.3/32, ubest/mbest: 1/0
*via 10.1.1.6, Eth1/2, [110/41], 2d10h, ospf-n9k-1, intra
4.4.4.4/32, ubest/mbest: 1/0
*via 10.1.1.10, Eth1/3, [110/41], 2d10h, ospf-n9k-1, intra
View the N9K-2 OSPF routing table:
N9K-2# show ip route ospf
IP Route Table for VRF "default"
'*' denotes best ucast next-hop
'**' denotes best mcast next-hop
'[x/y]' denotes [preference/metric]
'%<string>' in via output denotes VRF <string>
1.1.1.1/32, ubest/mbest: 1/0
*via 10.1.1.1, Eth1/1, [110/41], 2d10h, ospf-n9k-2, intra
3.3.3.3/32, ubest/mbest: 1/0
*via 10.1.1.1, Eth1/1, [110/81], 2d10h, ospf-n9k-2, intra
4.4.4.4/32, ubest/mbest: 1/0
*via 10.1.1.1, Eth1/1, [110/81], 2d10h, ospf-n9k-2, intra
10.1.1.4/30, ubest/mbest: 1/0
*via 10.1.1.1, Eth1/1, [110/80], 2d10h, ospf-n9k-2, intra
10.1.1.8/30, ubest/mbest: 1/0
*via 10.1.1.1, Eth1/1, [110/80], 2d10h, ospf-n9k-2, intra
View the N9K-3 OSPF routing table:
N9K-3# show ip route ospf
IP Route Table for VRF "default"
'*' denotes best ucast next-hop
'**' denotes best mcast next-hop
'[x/y]' denotes [preference/metric]
'%<string>' in via output denotes VRF <string>
1.1.1.1/32, ubest/mbest: 1/0
*via 10.1.1.5, Eth1/1, [110/41], 2d10h, ospf-n9k-3, intra
2.2.2.2/32, ubest/mbest: 1/0
*via 10.1.1.5, Eth1/1, [110/81], 2d10h, ospf-n9k-3, intra
4.4.4.4/32, ubest/mbest: 1/0
*via 10.1.1.5, Eth1/1, [110/81], 2d10h, ospf-n9k-3, intra
10.1.1.0/30, ubest/mbest: 1/0
*via 10.1.1.5, Eth1/1, [110/80], 2d10h, ospf-n9k-3, intra
10.1.1.8/30, ubest/mbest: 1/0
*via 10.1.1.5, Eth1/1, [110/80], 2d10h, ospf-n9k-3, intra
View the N9K-4 OSPF routing table:
N9K-4# show ip route ospf
IP Route Table for VRF "default"
'*' denotes best ucast next-hop
'**' denotes best mcast next-hop
'[x/y]' denotes [preference/metric]
'%<string>' in via output denotes VRF <string>
1.1.1.1/32, ubest/mbest: 1/0
*via 10.1.1.9, Eth1/1, [110/41], 2d10h, ospf-n9k-4, intra
2.2.2.2/32, ubest/mbest: 1/0
*via 10.1.1.9, Eth1/1, [110/81], 2d10h, ospf-n9k-4, intra
3.3.3.3/32, ubest/mbest: 1/0
*via 10.1.1.9, Eth1/1, [110/81], 2d10h, ospf-n9k-4, intra
10.1.1.0/30, ubest/mbest: 1/0
*via 10.1.1.9, Eth1/1, [110/80], 2d10h, ospf-n9k-4, intra
10.1.1.4/30, ubest/mbest: 1/0
*via 10.1.1.9, Eth1/1, [110/80], 2d10h, ospf-n9k-4, intra
2.3.2 Configuring Underlay Multicast Network
- Multicast is enabled on the device’s interconnection interface and loopback interface.
N9K-1 Configuration:
feature pim ip pim rp-address 1.1.1.1 group-list 239.0.0.0/24 interface loopback0 ip pim sparse-mode interface Ethernet1/1 ip pim sparse-mode interface Ethernet1/2 ip pim sparse-mode interface Ethernet1/3 ip pim sparse-mode
N9K-2 Configuration:
feature pim ip pim rp-address 1.1.1.1 group-list 239.0.0.0/24 interface loopback0 ip pim sparse-mode interface Ethernet1/1 ip pim sparse-mode
N9K-3 Configuration:
feature pim ip pim rp-address 1.1.1.1 group-list 239.0.0.0/24 interface loopback0 ip pim sparse-mode interface Ethernet1/1 ip pim sparse-mode
N9K-4 Configuration:
feature pim ip pim rp-address 1.1.1.1 group-list 239.0.0.0/24 interface loopback0 ip pim sparse-mode interface Ethernet1/1 ip pim sparse-mode
Configuration verification:
- First, you should use the command “show ip pim neighbor” to check the multicast neighbor;
- The complete multicast routing table will be available only when BUM packets trigger multicast traffic. The following multicast routing table is for reference.
View the N9K-1 Multicast routing table:
N9K-1# show ip mroute
IP Multicast Routing Table for VRF "default"
(*, 232.0.0.0/8), uptime: 06:25:14, pim ip
Incoming interface: Null, RPF nbr: 0.0.0.0
Outgoing interface list: (count: 0)
(*, 239.0.0.1/32), uptime: 06:11:39, pim ip
Incoming interface: loopback0, RPF nbr: 1.1.1.1
Outgoing interface list: (count: 3)
Ethernet1/1, uptime: 00:00:49, pim
Ethernet1/2, uptime: 00:00:55, pim
Ethernet1/3, uptime: 00:01:02, pim
(2.2.2.2/32, 239.0.0.1/32), uptime: 06:11:18, pim mrib ip
Incoming interface: Ethernet1/1, RPF nbr: 10.1.1.2, internal
Outgoing interface list: (count: 3)
Ethernet1/1, uptime: 00:00:49, pim, (RPF)
Ethernet1/2, uptime: 00:00:55, pim
Ethernet1/3, uptime: 00:01:02, pim
(3.3.3.3/32, 239.0.0.1/32), uptime: 06:11:06, pim mrib ip
Incoming interface: Ethernet1/2, RPF nbr: 10.1.1.6, internal
Outgoing interface list: (count: 3)
Ethernet1/1, uptime: 00:00:49, pim
Ethernet1/2, uptime: 00:00:55, pim, (RPF)
Ethernet1/3, uptime: 00:01:02, pim
(4.4.4.4/32, 239.0.0.1/32), uptime: 06:10:58, pim mrib ip
Incoming interface: Ethernet1/3, RPF nbr: 10.1.1.10, internal
Outgoing interface list: (count: 3)
Ethernet1/3, uptime: 00:00:39, pim, (RPF)
Ethernet1/1, uptime: 00:00:49, pim
Ethernet1/2, uptime: 00:00:55, pim
View the N9K-2 Multicast routing table:
N9K-2# show ip mroute
IP Multicast Routing Table for VRF "default"
(*, 232.0.0.0/8), uptime: 06:26:48, pim ip
Incoming interface: Null, RPF nbr: 0.0.0.0
Outgoing interface list: (count: 0)
(*, 239.0.0.1/32), uptime: 06:13:07, ip pim nve
Incoming interface: Ethernet1/1, RPF nbr: 10.1.1.1
Outgoing interface list: (count: 1)
nve1, uptime: 00:02:16, nve
(2.2.2.2/32, 239.0.0.1/32), uptime: 06:13:07, mrib ip pim nve
Incoming interface: loopback0, RPF nbr: 2.2.2.2
Outgoing interface list: (count: 1)
Ethernet1/1, uptime: 00:02:29, pim
View the N9K-3 Multicast routing table:
N9K-3# show ip mroute
IP Multicast Routing Table for VRF "default"
(*, 232.0.0.0/8), uptime: 06:26:50, pim ip
Incoming interface: Null, RPF nbr: 0.0.0.0
Outgoing interface list: (count: 0)
(*, 239.0.0.1/32), uptime: 06:13:15, ip pim nve
Incoming interface: Ethernet1/1, RPF nbr: 10.1.1.5
Outgoing interface list: (count: 1)
nve1, uptime: 00:02:36, nve
(3.3.3.3/32, 239.0.0.1/32), uptime: 06:13:15, mrib ip pim nve
Incoming interface: loopback0, RPF nbr: 3.3.3.3
Outgoing interface list: (count: 1)
Ethernet1/1, uptime: 00:02:43, pim
View the N9K-4 Multicast routing table:
N9K-4# show ip mroute
IP Multicast Routing Table for VRF "default"
(*, 232.0.0.0/8), uptime: 06:27:20, pim ip
Incoming interface: Null, RPF nbr: 0.0.0.0
Outgoing interface list: (count: 0)
(*, 239.0.0.1/32), uptime: 06:13:47, ip pim nve
Incoming interface: Ethernet1/1, RPF nbr: 10.1.1.9
Outgoing interface list: (count: 1)
nve1, uptime: 00:03:21, nve
(4.4.4.4/32, 239.0.0.1/32), uptime: 06:13:47, mrib ip pim nve
Incoming interface: loopback0, RPF nbr: 4.4.4.4
Outgoing interface list: (count: 1)
Ethernet1/1, uptime: 00:03:14, pim
2.3.3 Configuring Overlay Network
- The same VNI is added to the same multicast group. In this experiment, the multicast group is 239.0.0.1.
N9K-2 Configuration:
vlan 10
vn-segment 10010
interface nve1
no shutdown
source-interface loopback0
member vni 10010
mcast-group 239.0.0.1
N9K-3 Configuration:
vlan 10
vn-segment 10010
interface nve1
no shutdown
source-interface loopback0
member vni 10010
mcast-group 239.0.0.1
N9K-4 Configuration:
vlan 10
vn-segment 10010
interface nve1
no shutdown
source-interface loopback0
member vni 10010
mcast-group 239.0.0.1
Configuration verification:
Check the VNI and Peers status of N9K-2 NVE:
N9K-2# show nve vni
Codes: CP - Control Plane DP - Data Plane
UC - Unconfigured SA - Suppress ARP
SU - Suppress Unknown Unicast
Xconn-Crossconnect
MS-IR - Multisite Ingress Replication
Interface VNI Multicast-group State Mode Type [BD/VRF] Flags
--------- -------- ----------------- ----- ---- ------- ---------------
nve1 10010 239.0.0.1 Up DP L2 [10]
N9K-2# show nve peers
N9K-2#
Check the VNI and Peers status of N9K-3 NVE:
N9K-3# show nve vni
Codes: CP - Control Plane DP - Data Plane
UC - Unconfigured SA - Suppress ARP
SU - Suppress Unknown Unicast
Xconn-Crossconnect
MS-IR - Multisite Ingress Replication
Interface VNI Multicast-group State Mode Type [BD/VRF] Flags
--------- -------- ----------------- ----- ---- ------- ---------------
nve1 10010 239.0.0.1 Up DP L2 [10]
N9K-3# show nve peers
N9K-3#
Check the VNI and Peers status of N9K-4 NVE:
N9K-4# show nve vni
Codes: CP - Control Plane DP - Data Plane
UC - Unconfigured SA - Suppress ARP
SU - Suppress Unknown Unicast
Xconn-Crossconnect
MS-IR - Multisite Ingress Replication
Interface VNI Multicast-group State Mode Type [BD/VRF] Flags
--------- -------- ----------------- ----- ---- ------- ---------------
nve1 10010 239.0.0.1 Up DP L2 [10]
N9K-4# show nve peers
N9K-4#
It can be seen from the above results that there is currently no VxLAN tunnel established between VTEPs.
2.4 Experimental verification
2.4.1 PC IP configuration
PC1 configuration:
VPCS> show ip all NAME IP/MASK GATEWAY MAC DNS VPCS1 172.16.1.1/24 0.0.0.0 00:50:79:66:68:05
PC2 configuration:
VPCS> show ip all NAME IP/MASK GATEWAY MAC DNS VPCS1 172.16.1.2/24 0.0.0.0 00:50:79:66:68:06
PC3 configuration:
VPCS> show ip all NAME IP/MASK GATEWAY MAC DNS VPCS1 172.16.1.3/24 0.0.0.0 00:50:79:66:68:07
2.4.2 Trigger traffic
PC1 triggers traffic:
VPCS> ping 172.16.1.2 host (172.16.1.2) not reachable VPCS> ping 172.16.1.2 84 bytes from 172.16.1.2 icmp_seq=1 ttl=64 time=44.744 ms 84 bytes from 172.16.1.2 icmp_seq=2 ttl=64 time=49.071 ms 84 bytes from 172.16.1.2 icmp_seq=3 ttl=64 time=34.025 ms 84 bytes from 172.16.1.2 icmp_seq=4 ttl=64 time=43.254 ms 84 bytes from 172.16.1.2 icmp_seq=5 ttl=64 time=32.700 ms VPCS> ping 172.16.1.3 84 bytes from 172.16.1.3 icmp_seq=1 ttl=64 time=45.851 ms 84 bytes from 172.16.1.3 icmp_seq=2 ttl=64 time=47.016 ms 84 bytes from 172.16.1.3 icmp_seq=3 ttl=64 time=44.488 ms 84 bytes from 172.16.1.3 icmp_seq=4 ttl=64 time=43.073 ms 84 bytes from 172.16.1.3 icmp_seq=5 ttl=64 time=65.783 ms
PC2 triggers traffic:
VPCS> ping 172.16.1.3 host (172.16.1.3) not reachable VPCS> ping 172.16.1.3 84 bytes from 172.16.1.3 icmp_seq=1 ttl=64 time=34.228 ms 84 bytes from 172.16.1.3 icmp_seq=2 ttl=64 time=27.838 ms 84 bytes from 172.16.1.3 icmp_seq=3 ttl=64 time=62.914 ms 84 bytes from 172.16.1.3 icmp_seq=4 ttl=64 time=47.581 ms 84 bytes from 172.16.1.3 icmp_seq=5 ttl=64 time=25.724 ms
2.4.3 Check VxLAN Tunnel
N9K-2 VxLAN tunnel:
N9K-2# show nve peers Interface Peer-IP State LearnType Uptime Router-Mac --------- --------------- ----- --------- -------- ---- ------------- nve1 3.3.3.3 Up DP 00:02:30 n/a nve1 4.4.4.4 Up DP 00:02:20 n/a
N9K-3 VxLAN tunnel:
N9K-3# show nve peers Interface Peer-IP State LearnType Uptime Router-Mac --------- --------------- ----- --------- -------- ---- ------------- nve1 2.2.2.2 Up DP 00:02:42 n/a nve1 4.4.4.4 Up DP 00:02:14 n/a
N9K-4 VxLAN tunnel:
N9K-4# show nve peers Interface Peer-IP State LearnType Uptime Router-Mac --------- --------------- ----- --------- -------- ---- ------------- nve1 2.2.2.2 Up DP 00:02:55 n/a nve1 3.3.3.3 Up DP 00:02:28 n/a
It can be seen from the above results that the VxLAN tunnel between VTEPs will be automatically established after traffic triggering.
2.4.4 Check VxLAN MAC address table
N9K-2 MAC address table:
N9K-2# show system internal l2fwder mac
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
VLAN MAC Address Type age Secure NTFY Ports
--------- + -------------- + -------- + --------- + --- --- + ---- + ------------------
* 10 0050.7966.6805 dynamic 00:00:58 F F Eth1/2
* 10 0050.7966.6806 dynamic 00:00:58 F F (0x47000001) nve-peer1
3.3.3.3
* 10 0050.7966.6807 dynamic 00:00:56 F F (0x47000002) nve-peer2
4.4.4.4
N9K-3 MAC address table:
N9K-3# show system internal l2fwder mac
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
VLAN MAC Address Type age Secure NTFY Ports
--------- + -------------- + -------- + --------- + --- --- + ---- + ------------------
* 10 0050.7966.6805 dynamic 00:01:25 F F (0x47000001) nve-peer1
2.2.2.2
* 10 0050.7966.6806 dynamic 00:01:25 F F Eth1/2
* 10 0050.7966.6807 dynamic 00:01:16 F F (0x47000002) nve-peer2
4.4.4.4
N9K-4 MAC address table:
N9K-4# show system internal l2fwder mac
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
VLAN MAC Address Type age Secure NTFY Ports
--------- + -------------- + -------- + --------- + --- --- + ---- + ------------------
* 10 0050.7966.6805 dynamic 00:01:28 F F (0x47000001) nve-peer1
2.2.2.2
* 10 0050.7966.6806 dynamic 00:01:19 F F (0x47000002) nve-peer2
3.3.3.3
* 10 0050.7966.6807 dynamic 00:01:27 F F Eth1/2
For detailed learning process of MAC address, please refer to “Experiment 1: Implementing Cisco VxLAN based on static Ingress Replication”.
2.5 Message Analysis
2.5.1 BUM message analysis
- Capture packets on the E1/1 port of N9K-2;
- Clear the ARP tables of PC1 and PC2, and ping PC2 from PC1.
Clear the ARP table of PC1:
VPCS> arp 00:50:79:66:68:06 172.16.1.2 expires in 118 seconds VPCS> clear arp VPCS>arp arp table is empty VPCS>
Clear the ARP table of PC2:
VPCS> arp 00:50:79:66:68:05 172.16.1.1 expires in 93 seconds VPCS> clear arp VPCS>arp arp table is empty VPCS>
BUM packet capture:
Take the ARP request message as an example
image.png
Multicast forwarding instructions:
- On N9K-1, the PIM RP, for data packets from 2.2.2.2 and destined for 239.0.0.1, N9K-1 will forward the data packet to the E1/2 and E1/3 interfaces;
- Similarly, if a data packet goes to 239.0.0.1 from any source, the data packet will be forwarded to all other VTEPs that join the multicast group 239.0.0.1;
- Different from implementing VxLAN based on Static Ingress Replication, BUM traffic in VxLAN based on Multicast is transmitted by Underlay’s multicast network;
- Best practice: Use Anycast RP to achieve load balancing and redundancy of RP (Anycast RP is not used in this experiment). The following figure is an example of Anycast RP configuration on a Cisco Nexus switch:
image.png
2.5.2 Unicast packet analysis
- Capture packets on the E1/1 port of N9K-2;
Unicast packet capture:
Take ARP reply message as an example
image.png
3. Centralized gateway
- Goal: N9K-2 serves as a centralized gateway and changes the IP of PC3 to 172.16.2.1 so that PC3 can communicate with PC1 and PC2;
- The external routing device as a gateway is no longer demonstrated. For external routing devices as a gateway, please refer to Experiment 1;
- Packet capture is no longer demonstrated.
Change the configuration of N9K-2:
feature interface-vlan
vlan 20
vn-segment 10020
interfaceVlan10
no shutdown
IP address 172.16.1.254/24
interfaceVlan20
no shutdown
IP address 172.16.2.254/24
interface nve1
member vni 10020
mcast-group 239.0.0.2
Change N9K-4 configuration:
vlan 20
vn-segment 10020
interface nve1
no member vni 10010
member vni 10020
mcast-group 239.0.0.2
interface Ethernet1/2
switchport access vlan 20
Change PC1 configuration – add gateway:
VPCS>ip 172.16.1.1 255.255.255.0 172.16.1.254 Checking for duplicate address... PC1: 172.16.1.1 255.255.255.0 gateway 172.16.1.254
Change PC2 configuration – add gateway:
VPCS>ip 172.16.1.2 255.255.255.0 172.16.1.254 Checking for duplicate address... PC1: 172.16.1.2 255.255.255.0 gateway 172.16.1.254
Change PC3 configuration-modify IP:
VPCS>ip 172.16.2.1 255.255.255.0 172.16.2.254 Checking for duplicate address... PC1: 172.16.2.1 255.255.255.0 gateway 172.16.2.254
Test:
Ping PC1 from PC3
VPCS> ping 172.16.1.1 84 bytes from 172.16.1.1 icmp_seq=1 ttl=63 time=44.051 ms 84 bytes from 172.16.1.1 icmp_seq=2 ttl=63 time=52.670 ms 84 bytes from 172.16.1.1 icmp_seq=3 ttl=63 time=94.949 ms 84 bytes from 172.16.1.1 icmp_seq=4 ttl=63 time=48.976 ms 84 bytes from 172.16.1.1 icmp_seq=5 ttl=63 time=50.364 ms
Ping PC2 from PC3
VPCS> ping 172.16.1.2 84 bytes from 172.16.1.2 icmp_seq=1 ttl=63 time=66.403 ms 84 bytes from 172.16.1.2 icmp_seq=2 ttl=63 time=68.189 ms 84 bytes from 172.16.1.2 icmp_seq=3 ttl=63 time=67.867 ms 84 bytes from 172.16.1.2 icmp_seq=4 ttl=63 time=86.699 ms 84 bytes from 172.16.1.2 icmp_seq=5 ttl=63 time=75.751 ms
Ping PC1 from PC2
VPCS> ping 172.16.1.1 84 bytes from 172.16.1.1 icmp_seq=1 ttl=64 time=41.983 ms 84 bytes from 172.16.1.1 icmp_seq=2 ttl=64 time=46.274 ms 84 bytes from 172.16.1.1 icmp_seq=3 ttl=64 time=40.682 ms 84 bytes from 172.16.1.1 icmp_seq=4 ttl=64 time=51.736 ms 84 bytes from 172.16.1.1 icmp_seq=5 ttl=64 time=44.748 ms
If the centralized gateway is configured and checked correctly, if the connection fails, try saving and restarting the N9K!
4. Summary
Advantages of VxLAN based on Static Ingress Replications:
- Controlled deployment of VTEP;
- Simplify the troubleshooting process.
Disadvantages of implementing VxLAN based on Static Ingress Replications:
- Increased configuration and maintenance burden;
- Each peer must be manually configured on each VTEP, which is prone to configuration errors.
Advantages of VxLAN based on Multicast:
- Reduce configuration and maintenance burden;
- Flexible scalability;
- Effectively reduces the VTEP uplink bandwidth occupation, because the VTEP only needs to send a copy of the BUM traffic to the RP, and the RP forwards it to other VTEPs;
- The configuration is simple and VxLAN tunnels are automatically established after traffic is triggered.
Disadvantages of implementing VxLAN based on Multicast:
- Each VNI uses one multicast group;
- Using multicast protocols increases troubleshooting complexity.