Dell Force10 Z9000 FTOS Configuration Guide for Z9000 System - Page 529

Microsoft Clustering e Microsoft Clustering is supported only on platform: Microsoft Clustering allows multiple servers using Microsoft Windows to be represented by one MAC address and IP address in order to provide transparent failover or balancing. FTOS does not recognize server clusters by default; it must be configured to do so. Default Behavior When an ARP request is sent to a server cluster, either the active server or all of the servers send a reply, depending on the cluster configuration. If the active server sends a reply, the Dell Force10 switch learns the active server's MAC address. If all servers reply, the switch registers only the last received ARP reply, and the switch learns one server's actual MAC address (Figure 24-4); the virtual MAC address is never learned. Since the virtual MAC address is never learned, traffic is forwarded to only one server rather than the entire cluster, and failover and balancing are not preserved (Figure 24-5). Figure 24-4. Server Clustering: Multiple ARP Replies Source MAC: MACS1 Destination MAC: MACClient Type: 0x0806 Source IP: IPS1 Source MAC: MACCluster Microsoft Server Cluster: IPCluster MACCluster Server1: IPS1 MACS1 Server2: IPS2 MACS2 Server3: IPS3 MACS3 Ethernet Frame Header Last ARP Reply VLAN 1 ARP Reply Pad CRC Client Server4: IPS4 MACS4 fnC0027mp Layer 2 | 529