Dell PowerEdge R720xd Dell High Availability and Disaster Recovery Solutions U - Page 14

Dell High Availability and Disaster Recovery Solutions Using Microsoft SQL Server 2012 AlwaysOn Availability Groups Advantages and limitations of implementing AVG on shared storage Advantages:  Cost effective HA and DR solution for Enterprise Customers  Instance level protection using FCIs  Support of multi-subnet FCI clustering enables a DR solution using AlwaysOn with multi-subnet FCI  Flexible failover policy for granular trigger events for automatic failovers  Support for variety of storage types and configurations at each site (iSCSI, FC, SAS etc.)  May benefit from enhanced SAN features Limitations:  No Automatic failover/failback support for FCI when it is combined with AVG functionality AVG deployments on hybrid (HDD and SSD) storage In HA and DR solutions, it is always a good practice to use high performing drives such as SSDs in the primary site to get faster failover benefits and high performing databases within the primary site. Dell 12th generation servers (such as the R720 and R820) come with support for front-loading PCIe SSD drives. Benefits Dell™ PowerEdge R720 and R820 servers support up to four 2.5-inch 350G front-access PCIe SSDs drives. Figure 7 shows a possible deployment of AlwaysOn Availability Groups on the PCIe SSDs drives of Dell PowerEdge servers. Figure 7. AVG deployments on SSD and HDD 14