Do we need SQL Server cluster instances to configure always on?

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Do we need SQL Server cluster instances to configure always on?

Deploying Always On availability groups requires a Windows Server Failover Cluster (WSFC). To be enabled for Always On availability groups, an instance of SQL Server must reside on a WSFC node, and the WSFC and node must be online.

What is FCI in SQL Server?

An FCI is a single instance of SQL Server that is installed across Windows Server Failover Clustering (WSFC) nodes and, possibly, across multiple subnets.

What is SQL failover cluster instance?

An Always On Failover Cluster Instance (FCI) is a SQL Server instance that is installed across nodes in a WSFC. This type of instance depends on resources for storage and virtual network name.

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How long does SQL failover take?

While failover itself takes only a few seconds, the service will take at least 1 hour to activate it (RTO). This is necessary to ensure that the failover is justified by the scale of the outage. Also, the failover may result in small data loss (RPO) due to the nature of asynchronous replication.

What is the difference between clustering and AlwaysOn?

An SQL AlwaysOn failover cluster instance provides high availability and disaster recovery at the SQL Server level. AlwaysOn Availability Groups (AAG) provide high availability and disaster recovery at SQL database level. An AlwaysOn node manages backups of availability databases.

What is SQL Server AAG?

SQL Server AlwaysOn is a marketing term which refers to the high availability and disaster recovery solution introduced when SQL Server 2012 was launched. To be more specific, SQL Server AlwaysOn consists of two technologies: AlwaysOn Failover Clustering Instances (AlwaysOn FCI)

What is the difference between AlwaysOn and clustering in SQL Server?

How do I ensure high availability in SQL Server?

So let’s get stuck in.

  1. Replication. Let’s start with a feature which often comes up in the discussion: the replication feature within Microsoft SQL Server.
  2. Log Shipping. Okay, let’s get the obvious out of the way…
  3. Mirroring.
  4. Always On Failover Clustering.
  5. Always On Availability Groups.
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Why is it better to use cluster aware roles instead of generic applications or services for high availability applications?

Why is it better to use cluster-aware roles instead of generic applications or services for high-availability applications? The cluster might not know whether the generic application failed. You need to install the clustered role on the nodes in the target cluster.

How do I know if SQL Server is always on status?

The feature within SSMS for monitoring Availability groups is the Always On Dashboard. This main dashboard can be accessed by right clicking on the “Availability Groups” folder under the “Always On High Availability” folder in Object Explorer.

How many synchronous secondary replicas can I have?

To configure an availability group for automatic failover, you need to set both the current primary replica and at least one secondary replica to synchronous-commit mode with automatic failover. You can have up to three automatic failover replicas.

What is SQL AAG?

A read-scale availability group is a group of databases that are copied to other instances of SQL Server for read-only workload. An availability group supports one set of primary databases and one to eight sets of corresponding secondary databases. Secondary databases are not backups.

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Does SQL server failover cluster instance (FCI) need shared storage?

However, if you use a SQL Server failover cluster instance (FCI) to host one or more availability replicas, each of those FCIs will require shared storage as per standard SQL Server failover cluster instance installation.

How do I enable always on availability groups in SQL Server?

To be enabled for Always On availability groups, an instance of SQL Server must reside on a WSFC node, and the WSFC and node must be online. Furthermore, each availability replica of a given availability group must reside on a different node of the same WSFC.

Is SQL Server always on availability group dependent on failover clustering?

Also, though Always On availability groups is not dependent upon SQL Server Failover Clustering, you can use a failover clustering instance (FCI) to host an availability replica for an availability group.

Can a 2-node FCI failover be automatic?

If not and if you have a 2-Node FCI and each node has a local SAN Disk can failover be automatic and will the whole instance fail… Stack Exchange Network