High Availability - SQL Cluster This session is intended to give an overview of Failover Clustering with regards to SQL Server - Presentation Title shouldn’t take more than 30 sec.

About Me Tonatiuh Islas SQL DBA Analyst at Flex. Trajectory Contact SQL DBA Advisor at Dell Services Mexico. SQL DBA at Ryder Mexico. Primary SQL DBA at Bank of America. Contact Islas.tonatiuh@gmail.com This presentation won’t take more than 2 min.

Agenda High Availability (HA) vs Disaster recovery (DR) SQL Server’s High Availability Technologies Introduction to Windows failover cluster Components on SQL and Windows Failover Cluster (Quorum models, networks for clustering and basic storage configuration) SQL Clustering Architecture Differences between WSFC and FCI Installing SQL Server on a Windows cluster Administering SQL Server on a cluster Demo Q&A This slide won’t take more than 1 minute REMEMBER: Questions and Answers at the end of the presentation.

High Availability.- Definition and nines of availability Availability is traditionally measured according the percentage of time that the system is available to its end users. Refers to solutions that are more local in nature and generally tolerate smaller amounts of data loss and downtime. Percentage of availability = ((total elapsed time – sum of downtime)/total elapsed time). “Nines of availability” Percentage Availability Dowtime per year Downtime per Month Downtime per Week 99.0% 3.65 Days 7.30 hrs 1.68 hrs 99.9% 8.76 hrs 43.8 mins 10.1 mins 99.99% 52.6 mins 4.38 mins 1.01 mins 99.999% 5.26 mins 26.28 secs 6.06 sec The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

High Availability.- Factors Influencing Availability Personnel Factors. Human error stems from two main sources: administrative errors and end user errors. Fixed hiring the best and most qualified personnel getting a regular training routine. Operational Factors. Inefficient internal processes. Fixed establishing efficient and standardized operational procedures can eliminate unnecessary downtime. Documentation and standardized hardware along with software configurations. Technical Factors. Unplanned downtime and planned downtime. Unplanned downtime is further complicated by many factors like SLAs and disaster recovery plans. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Disaster Recovery. A disaster is an event that causes data loss or any serious business disruption. Causes of a disaster can be numerous: power failure, hardware failure, virus attack, natural disaster, human error, etc. Disaster recovery plan types include the following: A communication plan. Instructions for contacting the people involved in the response to the disaster. Information about who owns the administration of the plan. A checklist of required tasks for each recovery scenario The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

High Availability VS Disaster recovery. HA is the measurement of a system’s ability to remain accessible in the event of a system component failure. DR is the process by which a system is restored to a previous acceptable state, after a natural or man-made disaster. A notable difference is that with HA there is, generally, no loss of service (implemented by building in multiple levels of fault tolerance). HA uses SLAs (expected for your business and DR uses RTO (Recovery Time Objective) and RPO (Recovery Point Objective). The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

SQL Server’s High Availability Technologies. Windows Failover Clustering. Windows failover clustering provides server-level protection from both unplanned and planned downtime. SQL uses the Windows cluster technology were the main idea is the usage of shared storage and “nodes” The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

SQL Server’s High Availability Technologies. Database Mirroring . Database mirroring provides database-level protection from unplanned downtime. Data corruption can be handled in an easy way. The witness serves as a monitor. It detects if the principal database is not available and tells the mirror database to become the principal in the event that the original principal cannot be contacted The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

SQL Server’s High Availability Technologies. Log Shipping . Log shipping is a high-availability and disaster-recovery solution that can be used to protect against unplanned downtime. Like database mirroring, log shipping works by first restoring a full backup of the primary database to a backup server. Then transaction log backups are periodically sent from the primary server’s database and applied to the database on the backup server. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

SQL Server’s High Availability Technologies. Peer-to-Peer Replication . Peer-to-peer transactional replication is another data replication technology that can be used to protect against unplanned downtime. Peer-to-peer transactional replication is designed for bidirectional replication and high availability scenarios. One advantage to using replication is that the peer servers are continually available. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

SQL Server’s High Availability Technologies. Database Snapshots. Database snapshots allow you to quickly restore a database to a previous point in time. Database snapshots create copies (or “snapshots”) of a database without the overhead of performing a physical copy of the entire database. The database snapshot makes a copy of the original database schema. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

SQL Server’s High Availability Technologies. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Windows failover cluster. A failover cluster solution must meet the following hardware requirements: Storage must be attached to the nodes in the cluster, if the solution is using shared storage. Device controllers or appropriate adapters for the storage can be Serial Attached SCSI (SAS), Fibre Channel, Fibre Channel over Ethernet (FcoE), or iSCSI. The complete cluster configuration (servers, network, and storage) must pass all tests in the Validate a Configuration Wizard. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Windows failover cluster. Cluster service. The essential software component that controls all aspects of server cluster or failover cluster operations. Each node in a failover cluster or server cluster runs one instance of the Cluster service. LAN Switch NIC Teaming 1 2 3 The DLL contains the resource-specific code that is necessary to provide high availability for one or more resource types. Each resource type exposes two types of health detection checks LooksAlive is a lightweight, more frequent check. IsAlive is run less frequently to do a deeper check that the service is available 1 2 3 Nic Nic non routable ip addresses heartbeat Switch Switch The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text Storage Ports

Windows failover cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Windows failover cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Windows failover cluster. Network Public Normal LAN connectivity Heartbeat Used for Cluster communications between nodes Storage (iSCSI) TCP connectivity to iSCSI storage The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Windows failover cluster. Network Nic Teaming is used for load balancing and Failover. In the past, NIC teaming was handled by the NIC vendor’s driver and management software. One of the new features in Windows Server 2012 is Microsoft NIC Teaming The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text Nic Teaming (Virtual) 1 2 3 NFT. Fault Tolerance NLB. Load Balance Nic card

Windows failover cluster. Quorum Why quorum is necessary? When network problems occur, they can interfere with communication between cluster nodes. A small set of nodes might be able to communicate together across a functioning part of a network but not be able to communicate with a different set of nodes in another part of the network. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Windows failover cluster. Quorum Models Considerations ODD/EVEN Local/Remote The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Windows failover cluster. Quorum New in Server 2012/R2 Dynamic Quorum Introduced in Windows Server 2012 Implements “Last Man Standing” Dynamically removes voting rights Dynamic Witness Introduced in Windows Server 2012 R2 Cluster decides whether to use witness The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Windows failover cluster. MSDTC MSDTC is a component of Windows Server and is leveraged by some SQL Server features and applications to coordinate transactions across multiple servers The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Topology and Architecture of a SQL Server Cluster. SQL Clustering components: Two or more nodes Shared Storage Quorum CNO (Cluster Name Object) and CLUSTERNAME$ in AD Cluster IP and Network Name SQL Virtual Network Name and IP SQL Clustered Installation The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Topology and Architecture of a SQL Server Cluster. Common SQL Server Failover Deployments: • Single failover cluster instance two-node cluster. • Multi-instance cluster: o All nodes with active instances. o n+1 (n instances with one spare node). • Multi-site failover cluster instance. • Guest failover cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Topology and Architecture of a SQL Server Cluster. A SQL Server failover cluster instance that is installed on a Windows Server failover cluster is similar to a stand-alone SQL Server instance that does not use Windows Server failover clustering. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Installing a SQL Server Cluster. Prerequisites Enable “Failover Clustering” OS feature Present Shared Storage to all nodes Pre-stage cluster objects in AD (if needed) Ensure NIC’s for all networks are configured Create a WSFC in Windows Server and .Net framework 3.5 (or above) Obtain successful cluster validation report Perform SQL Server Clustered Installation “Add Node” to all secondary nodes The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Installing a SQL Server Cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Installing a SQL Server Cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Installing a SQL Server Cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Installing a SQL Server Cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Installing a SQL Server Cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Installing a SQL Server Cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Installing a SQL Server Cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Installing a SQL Server Cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Installing a SQL Server Cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Installing a SQL Server Cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Installing a SQL Server Cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Installing a SQL Server Cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Installing a SQL Server Cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Installing a SQL Server Cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Installing a SQL Server Cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Installing a SQL Server Cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Administering SQL Server on a cluster. Use “Failover Cluster Manager” For failover Look at cluster resources and dependencies What happens during failover Primary node SQL services are stopped Secondary SQL services start and gain control of shared storage All system/user DB’s live on shared storage The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Administering SQL Server on a cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

New Features in SQL Server 2012. Flexible Failover Policy Levels 0-5 (Default of 3) LooksAlive/IsAlive replaced by sp_server_diagnostics Support for multi-subnet clusters IP Binding using OR algorithm The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

New Features in SQL Server 2012. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

DEMO SQL Server on a cluster. The presenter has no more than 35 for presentation. The content must be accurate, no redundant. The presentation shouldn’t have excessive text More images than text

Q&A 5 minutes for Questions.