HP P4000 9.0 HP StorageWorks P4000 Multi-Site HA/DR Solution Pack User Guide - Page 10

In addition to setting up the Multi-Site clusters for data replication, it is important to set up the SAN managers for quorum correctly to ensure that in the event of a failure the system can be properly recovered. Maintaining quorum can be either an automated process or manually recovered by an Administrator. Table 2 summarizes common Multi-Site SAN and manager configurations. Table 2 Common configurations of Multi-Site SANs and mangers Number of sites Cluster/site setup Total number of Failover Man- Site types managers of all types ager three physical sites Cluster spans two sites two physical sites, Cluster spans two with logical third site sites three physical sites Cluster spans three sites two physical sites Cluster spans two sites Min = three; Max = five In the third site Min = three; Max = five In the logical third site Min = three; Max = six Not used Min = three; Max = five Not used All sites are peer. All sites are peer. All sites are peer. One site is designated primary. Best practice In a cluster that spans multiple sites, run the same number of managers in each site. In a cluster that spans two sites, run a Failover Manager in a third site (physical or logical) that is not included in the cluster (Figure 2 on page 11). The one exception to this rule is the two-site configuration in which one site is configured as primary (Figure 5 on page 12). In this case, run a majority of the managers in the primary site. Sample configurations Figure 2 on page 11, Figure 3 on page 11, Figure 4 on page 12, and Figure 5 on page 12 illustrate best practice for four configurations. Note that management groups and Multi-Site clusters can have many more storage systems than are depicted here. These graphics however, illustrate the significant points of site-to-cluster mappings and the appropriate placement of managers. 10 Designing a Multi-Site SAN