Advantages And Limitations Of Implementing Avg On Shared Storage; Avg Deployments On Hybrid (Hdd And Ssd) Storage; Benefits; Figure 7. Avg Deployments On Ssd And Hdd - Dell PowerEdge External Media System 1434 Using Manual

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
th
12 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
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