SQLCAT: SQL Server HA and DR Design Patterns, Architectures, and Best Practices Using Microsoft SQL Server 2012 AlwaysOn Sanjay Mishra Program Manager Microsoft Corporation DBI316

Assumed Pre-requisites for this presentation: Basic knowledge of AlwaysOn Failover Cluster Instances (FCI) AlwaysOn Availability Groups (AG) Definition: For the purpose of this presentation High Availability (Local HA): Availability within a data center Disaster Recovery (DR): Availability across data centers

AlwaysOn ≠ Availability Groups AlwaysOn = { SQL Server Failover Cluster Instances, Availability Groups } Availability Groups ≠ Database Mirroring

SQL Server 2012 AlwaysOn HA+DR Design Pattern Solution Characteristics Corresponding Pre-SQL Server 2012 Solution 1 Multi-site Failover Cluster Instance (FCI) for HA and DR Shared Storage solution 1 1 Masked by storage replication Multi-site FCI using stretch VLAN 2 Availability Group for HA and DR Non-Shared Storage solution Database Mirroring for Local HA and Log Shipping for DR 3 Failover Cluster Instance for local HA + Availability Group for DR Combined Shared Storage and Non-Shared Storage Failover Cluster Instance for Local HA and Database Mirroring for DR

title Multi-site Failover Cluster Instance for HA and DR

Primary Site DR Site Node 1 Node 2 Node 3 Node 4 Windows Server Failover Cluster Storage Replication SQL-FCI ActivePassive SQL Server 2012 AlwaysOn HA+DR Solution Solution Characteristics Corresponding Pre-SQL Server 2012 Solution 1 Multi-site Failover Cluster Instance (FCI) for HA and DR ( s/archive/2011/12/22/sql-server alwayson_3a00_-multisite-failover- cluster-instance.aspx ) s/archive/2011/12/22/sql-server alwayson_3a00_-multisite-failover- cluster-instance.aspx Shared Storage solution 1 Instance Level HA (automatic) Instance Level DR (automatic 2 ) Uses storage replication 1 Masked by storage replication 2 Consider 3 rd data center Multi-site FCI using stretch VLAN

Multi-site Failover Cluster Instance Key Elements A single SQL Server failover cluster instance (FCI) providing HA as well as DR spanning across multiple sites (usually multiple subnets as well) Key components: Storage Storage level replication Cluster Enabler Provided by the storage vendor Work with your storage vendor to get the appropriate software and best practices Network Multi-subnet support in SQL Server configuration and engine Key improvement in SQL Server 2012 IP address OR dependency set within SQL Server setup SQL Engine skips binding to any IP’s which are not online at start-up RegisterAllProvidersIP for Network Name improves application failover time

Multi-site Failover Cluster Instance Deployment Considerations

title Availability Groups for HA and DR

SQL Server 2012 AlwaysOn HA+DR Solution Solution Characteristics Corresponding Pre-SQL Server 2012 Solution 2 Availability Group for HA and DR Non-Shared Storage solution (Group of) Database Level HA (automatic) (Group of) Database Level DR (manual 3 ) DR replica can be Active Secondary 3 DR is manual, if HA is chosen automatic. Consider 3 rd data center, if need automatic DR. Database Mirroring for Local HA and Log Shipping for DR

Availability Groups for HA and DR Deployment Considerations

Availability Groups for HA and DR Quorum Considerations

Note: The Fileshare Witness always has 1 vote. Quorum Model and Node Votes Node and Fileshare Majority Use the “Node and File Share Majority” quorum model with a protected file share witness.

Quorum Model and Node Votes Node Majority Add an additional voting node to the WSFC in the primary data center, and then use the “Node Majority” quorum model.

Quorum Model and Node Votes How to set / view To View Quorum Model Windows Failover Cluster Manager GUI PowerShell Cluster.exe SQL Server DMVs AlwaysOn Dashboard in SSMS To Change Quorum Model Windows Failover Cluster Manager GUI PowerShell Cluster.exe To View Node Votes PowerShell Cluster.exe SQL Server DMVs AlwaysOn Dashboard in SSMS To Change Node Votes PowerShell Cluster.exe

Recovering from a Disaster

Migration: From DBM+LS to AG Planning and Key Considerations

title Failover Cluster Instance for HA, and Availability Group for DR

FCI for HA + AG for DR SQL Server 2012 AlwaysOn HA+DR Solution Solution Characteristics Corresponding Pre-SQL Server 2012 Solution 3 Failover Cluster Instance for local HA + Availability Group for DR Combined Shared Storage and Non-Shared Storage Instance Level HA (automatic) (Group of) Database Level DR (manual) DR replica can be Active Secondary Asymmetric storage is the key to this solution Failover Cluster Instance for Local HA and Database Mirroring for DR

FCI for HA + AG for DR Deployment Considerations

FCI for HA + AG for DR Quorum Considerations

Note: The Fileshare Witness always has 1 vote. Quorum Model and Node Votes Example: Node and Fileshare Majority

Quorum Model and Node Votes How to set / view To View Quorum Model Windows Failover Cluster Manager GUI PowerShell Cluster.exe SQL Server DMVs AlwaysOn Dashboard in SSMS To Change Quorum Model Windows Failover Cluster Manager GUI PowerShell Cluster.exe To View Node Votes PowerShell Cluster.exe SQL Server DMVs AlwaysOn Dashboard in SSMS To Change Node Votes PowerShell Cluster.exe Note: Only cluster.exe can be used to set quorum model to “Node and (asymmetric) Disk Majority” or “(asymmetric) Disk Only”

Recovering from a Disaster

Migration: From FCI+DBM to FCI+AG Planning and Key Considerations

Summary

SQL Server 2012 AlwaysOn HA+DR Design Pattern Solution Characteristics Corresponding Pre-SQL Server 2012 Solution 1 Multi-site Failover Cluster Instance (FCI) for HA and DR Shared Storage solution 1 Instance Level HA (automatic) Instance Level DR (automatic 2 ) Uses storage replication Doesn’t require database to be in FULL recovery model 1 Masked by storage replication 2 Consider 3 rd data center Multi-site FCI using stretch VLAN 2 Availability Group for HA and DR Non-Shared Storage solution (Group of) Database Level HA (automatic) (Group of) Database Level DR (manual 3 ) DR replica can be Active Secondary Requires database to be in FULL recovery model 3 DR is manual, if HA is chosen automatic. Consider 3 rd data center, if need automatic DR. Database Mirroring for Local HA and Log Shipping for DR 3 Failover Cluster Instance for local HA + Availability Group for DR Combined Shared Storage and Non-Shared Storage Instance Level HA (automatic) (Group of) Database Level DR (manual) DR replica can be Active Secondary Requires database to be in FULL recovery model Asymmetric storage is the key to this solution Failover Cluster Instance for Local HA and Database Mirroring for DR

Sanjay Mishra

Connect. Share. Discuss. Learning Microsoft Certification & Training Resources TechNet Resources for IT Professionals Resources for Developers

Required Slide Complete an evaluation on CommNet and enter to win!

Scan the Tag to evaluate this session now on myTechEd Mobile Required Slide *delete this box when your slide is finalized Your MS Tag will be inserted here during the final scrub.