How do I ensure high availability in SQL Server?
At a high level, there are five main high availability options including a new feature set to be release with SQL Server 2012:
- Replication.
- Mirroring.
- Log Shipping.
- Clustering.
- AlwaysON.
What are high availability features in SQL Server?
It is the solution or process or technology to make the service or application or database availability 24×7 and 100% through needless and fault-tolerant components at the same location under either planned or unplanned outages.
How do you ensure high availability of a database?
Key Principles of High Availability
- Eliminate any single point of failure: Adding redundancy, so that the failure of any one part of the system does not lead to the collapse of the entire system.
- Reliable crossover: In a redundant system, the crossover point itself becomes a single point of failure.
What is SQL database architecture?
SQL Server database is a logical collection of data. Data is stored in two sets of files – Data Files and Log Files. An Extent consists of 8 – 8KB continuous pages and in similar manner the data file consists of extents. Log files store all modifications that are made to the database such as DDL, DML operations.
Which architecture does an SQL follow?
client-server architecture
Microsoft SQL Server is a client-server architecture. MS SQL Server process starts with the client application sending a request. The SQL Server accepts processes and replies to the request with the processed data.
What are the high availability solutions in SQL Server and differentiate them briefly?
There are 4 High Availability options in SQL Server 2008 that we will cover; Failover Clustering, Database Mirroring, Log Shipping and Replication. Each one has its own features and benefits.
What are high availability principles?
High availability (HA) is a characteristic of a system which aims to ensure an agreed level of operational performance, usually uptime, for a higher than normal period. For example, hospitals and data centers require high availability of their systems to perform routine daily activities.
How do you maintain high availability?
Here are some of the key resources you can implement to make high availability possible:
- Implement multiple application servers.
- Scaling and slaves matters.
- Spread out physically.
- Maintain a recurring online backup system along with hardware.
- Use of a virtualized server for zero-downtime recovery.
What is AlwaysOn SQL?
SQL Server AlwaysOn provides a high-availability and Disaster-recovery solution for SQL Server 2012. It makes use of existing SQL Server features, particularly Failover Clustering, and provides new capabilities such as availability groups. It aims to provide more granular control to achieve High Availability.
How is high availability implemented in SQL Server?
High availability is implemented using a technology similar to SQL Server Always On availability groups. The cluster includes a single primary replica that is accessible for read-write customer workloads, and up to three secondary replicas (compute and storage) containing copies of data.
What are the best practices for SQL Server?
Best practices for SQL Server Availability 1 Contrasting RPO and RTO Capabilities. 2 Failover Cluster Instance 3 Log Shipping. 4 To get the best availability, the Always On Availability Group cluster would have to be in an “Availability Set”, which ensures our back end maintenance does not take all of
Which is the best Oracle high availability solution?
Oracle Real Application Clusters Guard is Oracle’s premier high availability solution. It has been designed to address many of the causes of unplanned and planned downtime, to maximize database availability, and to minimize disruption to end users of the data services.
What does always on availability groups in SQL Server mean?
The Always On availability groups feature is a high-availability and disaster-recovery solution that provides an enterprise-level alternative to database mirroring. Introduced in SQL Server 2012 (11.x), Always On availability groups maximizes the availability of a set of user databases for an enterprise.