NLB Multicast Mode – Static ARP Resolution

• Since NLB packets are unconventional, meaning the IP address is Unicast while the MAC address of it is Multicast, switches and routers drop NLB packets.
• NLB Multicast Packets get dropped by routers and switches, causing the ARP tables of switches to not get populated with cluster IP and MAC address.
• Manual ARP Resolution of NLB cluster address is required on physical switch and router interfaces
• Cluster IP and MAC static resolution is set on each switch port that connects to ESX/ESXi host
• Virtual Switch NIC Team Policy > Notify Switches is set to Yes.
• If CDP (Cisco Discovery Protocol) is Enabled on ESX/ESXi and the Cisco Switch - you can determine proper switch ports connecting to ESX/ESXi via the vSphere/Virtual Infrastructure Client.

VMware ESXi 3.5.x Embedded
VMware vCenter Server 6.0.x
VMware ESX 4.1.x
VMware ESXi 4.0.x Embedded
VMware ESXi 4.1.x Installable
VMware vSphere ESXi 5.5
VMware ESXi 4.0.x Installable
VMware vSphere ESXi 5.0
VMware vSphere ESXi 5.1
VMware vCenter Server 5.5.x
VMware ESXi 3.5.x Installable
VMware vCenter Server 5.1.x
VMware ESX Server 3.5.x
VMware ESX 4.0.x
VMware vSphere ESXi 6.0
VMware vCenter Server 5.0.x
VMware ESXi 4.1.x Embedded

1. Telnet in to Cisco Switch Console and log in.
2. Run this command to enter Configuration mode:
   
   config t
   
   
3. STATIC ARP RESOLUTION Cisco Global command mode
   
   For example:
   
   arp [ip] [cluster multicast mac] ARPA
   arp 192.168.1.100 03bf.c0a8.0164 ARPA
   
   
4. STATIC MAC RESOLUTION Cisco Global command mode
   
   For example:
   
   mac-address-table static [cluster multicast mac] [vlan id] [interface]
   mac-address-table static 03bf.c0a8.0164 vlan 1 interface GigabitEthernet1/1 GigabitEthernet1/2
   GigabitEthernet1/15 GigabitEthernet1/16

For more information, see Sample Configuration - Network Load Balancing (NLB) Multicast Mode Configuration (1006558).Sample Configuration - Network Load Balancing (NLB) Multicast Mode Configuration
Ejemplo de configuración - Modo de multidifusión de equilibrio de carga de red (NLB) en una subred enrutada - Configuración de ARP estática de conmutador Cisco
Configuração de amostra - Modo multicast de balanceamento de carga de rede (NLB) sobre sub-rede roteada - Configuração Cisco Switch Static ARP
配置示例 - 基于路由子网的网络负载平衡 (NLB) 多播模式 - Cisco 交换机静态 ARP 配置
サンプル構成 - 経路指定サブネットを介したネットワーク ロード ラバンシング (NLB) のマルチキャスト モード - Cisco スイッチの静的 ARP 構成