What is the best version of SQL Server?
SQL Server 2019 is not released yet, so I would only recommend using it for testing purposes and to know the new functionality in testing environments. The best choice would be SQL Server 2017 which is a robust, stable version. For more information about the features of each version, refer to the following links:
What can you do using SQL Server?
What Can You Do With Microsoft SQL?
- Access Databases. SQL contains a series of commands that let you search and select records in a database. ...
- Manipulate Databases. A wide variety of SQL commands let you manipulate information that is stored in a Microsoft SQL database.
- Database Creation. SQL includes the capability to spawn new databases and alter database properties. ...
- Website Use. ...
How to check what SQL Server version you are using?
Using SQL Server file exe.
- Navigate to SQL Server installed folder. For Example “C:\Program Files\Microsoft SQL Server\MSSQL11.SGALDW\MSSQL\Binn”
- Right click on sqlservr.exe and select properties.
- Go to details tab and you will find information about SQL Server like Product name and Product Version.
How secure is SQL Server?
SQL Server provides a security architecture that is designed to allow database administrators and developers to create secure database applications and counter threats. The SQL Server security framework manages access to securable entities through authentication and authorization.
What is HA and DR in SQL Server?
SQL Server high availability (HA) is about providing service availability and 100% uptime through redundant and fault-tolerant components at the same location. Disaster Recovery (DR) is about providing service continuity and minimizing downtime through redundant & independent site in a distinct location.
What type of HA is available for SQL Server?
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.
What is HA in database?
A High Availability (HA) Database is a database system designed to operate continuously with no interruptions in service. So database errors and failures must be handled by automatically failing over to redundant nodes when problems occur.
Does SQL have high availability?
SQL Server Log Shipping is a Database-level High Availability Solution that is suitable for less mission-critical databases and offers a customizable recovery point and time. It is made up of one primary Database Server and one or more standby secondary servers for reporting purposes.
How does SQL HA work?
You can create an availability group for high availability (HA) or for read-scale. An HA availability group is a group of databases that fail over together. A read-scale availability group is a group of databases that are copied to other instances of SQL Server for read-only workload.
What is the difference between high availability and disaster recovery?
High Availability (HA)—refers to a system or component that is continuously operational for a desirably long period. Disaster Recovery (DR)—involves a set of policies and procedures to enable the recovery or continuation of vital infrastructure and systems following a natural or human-induced disaster.
What is HA and how IT works?
HA monitors whether sufficient resources are available in the cluster at all times in order to be able to restart virtual machines on different physical host machines in the event of host failure.
How do I ensure high availability in SQL Server?
There are mainly five options in MS SQL Server to setup high availability solution for the databases:Replication.Log Shipping.Mirroring.Clustering (Failover Cluster)AlwaysON Availability Groups (AG)
Why is high availability important?
High availability enables your IT infrastructure to continue functioning even when some of its components fail. High availability is of great significance for mission-critical systems, where a service disruption may lead to adverse business impact, resulting in additional expenses or financial losses.
How do you check if high availability is enabled in SQL Server?
In SQL Server Configuration Manager, click SQL Server Services, right-click SQL Server (
How do I set always on high availability?
Right click on the TCP/IP entry and select Enable. While you are still in SQL Server Configuration Manager, right click on SQL Server Services to open the Properties dialog box. Navigate to the AlwaysOn High Availability tab, and select Enable AlwaysOn Availability Groups checkbox.
What is difference between log shipping and mirroring?
Log shipping supports an unlimited number of secondary's for each primary database. Database mirroring can operate synchronously or asynchronously. If configured to operate synchronously, the transaction on the principal will not be committed until it is hardened to disk on the mirror.
What are the high availability options available from SQL Server 2008 onwards?
There are 4 High Availability options in SQL Server 2008 that we will cover; Failover Clustering, Database Mirroring, Log Shipping and Replication.
How do you check if high availability is enabled in SQL Server?
In SQL Server Configuration Manager, click SQL Server Services, right-click SQL Server (
What is high availability setup?
The purpose of an HA configuration is to reduce downtime when a zone or instance becomes unavailable. This might happen during a zonal outage, or when an instance runs out of memory. With HA, your data continues to be available to client applications. The HA configuration provides data redundancy.
What is disaster recovery in SQL Server?
SQL Server Disaster Recovery. The primary goal of Disaster Recovery is to provide service continuity in case of any geographical disasters by recovering or resuming the services from a geographically different location. DR can be either located in one or more locations in addition to the primary location.
Container with SQL Server instance on Kubernetes
Kubernetes 1.6 and later has support for storage classes, persistent volume claims, and the Azure disk volume type.
Next steps
To deploy SQL Server containers in Azure Kubernetes Service (AKS), see these examples:
What happens when SQL Server fails?
If the SQL Server availability group experiences a failover, the BizTalk Server databases on the availability group are temporarily unavailable.
What is the enclose body of SQL Agent job steps within IF block?
Enclose body of SQL Agent job steps within IF block (mentioned previously) to make sure they run only if the target is the primary replica.
What happens when BizTalk is unavailable?
If the BizTalk Server databases are unavailable, then an in-process instance of a BizTalk Server host is recycled until the connection to the SQL Server is restored. Once the connection to the SQL Server databases is restored, document processing resumes normally.
When configuring BizTalk Server and specifying the SQL server name, what is the listener name?
When configuring BizTalk Server and specifying the SQL server name, use the Availability Group’s listener name instead of the actual machine name. This creates the BizTalk databases, logins, and SQL Agent jobs on the current primary replica.
Does BizTalk support BAM DTS?
Starting with BizTalk Server 2020 and newer, high availablity for BAM DTS packages is supported using SSIS Catalog. Add the SSISDB database to the same availability group as the BizTalk Server databases. This configuration is shown in the following image, and recommended for BizTalk databases in Availability Groups:
How to add a database to an availability group?
To add a database to an availability group, the database must be an online, read-write database that exists on the server instance that hosts the primary replica. When you add a database, it joins the availability group as a primary database, while remaining available to clients.
What is availability group?
An availability group supports a replicated environment for a discrete set of user databases, known as availability databases. You can create an availability group for high availability (HA) or for read-scale. An HA availability group is a group of databases that fail over together. 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. Continue to back up your databases and their transaction logs on a regular basis.
When does availability replica resolve?
When the role of an availability replica is indeterminate, such as during a failover, its databases are temporarily in a NOT SYNCHRONIZING state. Their role is set to RESOLVING until the role of the availability replica has resolved. If an availability replica resolves to the primary role, its databases become the primary databases. If an availability replica resolves to the secondary role, its databases become secondary databases.
What is the goal of high availability?
The primary goal of high availability is to ensure service availability by minimizing the impact of downtime from either planned or unplanned activities. Almost all high availability techniques will have their infrastructure placed in a single geographic location and have the option to switch over automatically.
What is mirroring in SQL Server?
Database Mirroring is primarily an HA solution and included in this article for references but will be removed in later versions of SQL Server. Database Mirroring involves two servers. A Source database resides on a Source Server called the Principal Server, and the Destinatinon database, also called the Mirrored database, resides on a Destination Server called the Mirrored Server. The Witness Server is an optional third server that can help monitor the heartbeat of Mirroring between Principal and Mirror Server and can initiate automatic failover to the Mirrored Server when the mirroring is set to High Safety mode.
Can a business DR and HA be used together?
To conclude, Business Continuity can be achieved via both HA and DR solutions, and in several scenarios, both complement each other. You will need to determine the better HA and DR solutions to meet business requirements, and here are the key items to take home with you.
Can a HA failover cluster have multiple servers?
This HA plan will require configuring multiple servers in the same Windows Server Failover Cluster (WSFC) having a shared storage area network (SAN) on which one or more SQL Server user databases reside. Below is a diagrammatic representation of the Failover Cluster Instance HA solution.
What is always on dashboard?
The Always On Dashboard monitors Always On availability groups, availability replicas, and availability databases and evaluates results for Always On policies. For more information, see Use the Always On Dashboard (SQL Server Management Studio).
What is always on availability group?
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. An availability group supports a failover environment for a discrete set of user databases, known as availability databases, that fail over together. An availability group supports a set of read-write primary databases and one to eight sets of corresponding secondary databases. Optionally, secondary databases can be made available for read-only access and/or some backup operations.
What is the Add Database to Availability Group Wizard?
The Add Database to Availability Group Wizard adds one or more primary databases to an existing availability group. In some environments, this wizard can also automatically prepare the secondary databases and start data synchronization for each of them. For more information, see Use the Add Database to Availability Group Wizard (SQL Server).
What is quorum in SQL?
o In the context of SQL database mirroring or availability groups with automatic failover, quorum makes sure that a database is owned by only one partner or replica at a time.
What is a quorum in a computer?
· Quorum: Generally speaking, a quorum is the minimum number of members of an assembly, who must be present before the members can conduct business.
Is a database on secondary readable?
Considerations: - Database must be using the FULL recovery model. - Database on secondary is not writeable. - Database on secondary can be set as readable (Readable or READ-INTENT secondary options) - Note that the system databases master, tempdb, and model cannot be part of an AG.
How to configure high availability?
To configure a high-availability setup, place all participating SQL Server virtual machines in the same availability set to avoid application or data loss during a maintenance event . Only nodes in the same cloud service can participate in the same availability set. For more information, see Manage the availability of virtual machines.
How to have a disaster recovery solution for SQL Server?
You can have a disaster recovery solution for your SQL Server databases in Azure by using availability groups, database mirroring, or backup and restore with storage blobs.
How to use SQL Server as a passive replica?
To enable this benefit, go to your SQL Server virtual machine resource. Select Configure under Settings, and then choose the Disaster Recovery option under SQL Server License. Select the check box to confirm that this SQL Server VM will be used as a passive replica, and then select Apply to save your settings.
Can you have a high availability solution for SQL Server at a database level?
You can have a high-availability solution for SQL Server at a database level with Always On availability groups. You can also create a high-availability solution at an instance level with Always On failover cluster instances. For additional protection, you can create redundancy at both levels by creating availability groups on failover cluster instances.
Is SQL Server HADR only on Azure?
Most SQL Server HADR solutions are supported on virtual machines (VMs), as both Azure-only and hybrid solutions. In an Azure-only solution, the entire HADR system runs in Azure. In a hybrid configuration, part of the solution runs in Azure and the other part runs on-premises in your organization. The flexibility of the Azure environment enables you to move partially or completely to Azure to satisfy the budget and HADR requirements of your SQL Server database systems.
Can you use a VPN for SQL Server?
Depending on the technology that you use, a hybrid deployment might require a VPN tunnel with the Azure virtual network. The following sections show you some example deployment architectures.
Can SQL Server be disaster recovery?
You can have a disaster recovery solution for your SQL Server databases in a hybrid IT environment by using availability groups, database mirroring, log shipping, and backup and restore with Azure Blob storage.
What is the default port for availability group listener VNNs?
If you use the default port of 1433 for availability group listener VNNs, you will still need to ensure that no other services on the cluster node are using this port; otherwise this would cause a port conflict.
What happens when an availability group fails?
When an availability group failover occurs, existing persistent connections to the availability group are terminated and the client must establish a new connection in order to continue working with the same primary database or read-only secondary database. While a failover is occurring on the server side, connectivity to the availability group may fail, forcing the client application to retry connecting until the primary is brought fully back online.
What is a listener in SQL Server?
A listener allows a client to connect to a replica without having to know the physical instance name of the SQL Server. Since the listener routes traffic, the client connection string does not need to be modified after a failover occurs. An availability group listener consists of a Domain Name System (DNS) listener name, listener port designation, ...
Background and History
SQL Server 2016 AlwaysOn Availability Groups
- Deploying AlwaysOn Availability Groups requires a Windows Server Failover Clustering (WSFC) cluster. Each availability replica of a given availability group must reside on a different node of the same WSFC cluster. A WSFC resource group is created for every availability group that you create. The WSFC cluster monitors this resource group to evaluate the health of the primary repl…
Requirements
- BizTalk Server:
- SQL Server:
- Windows Server
References
Known Limitations
- These limitations are for BizTalk Server, SQL Server AlwaysOn Availability Group, and Azure Virtual Machines. These limitations may or may not get addressed in future. 1. Logins, SQL Agent Jobs, the SQL DB Mail profile, and accounts are not managed within Availability Groups. This requires manual modification in Jobs to make sure they run against the primary replica. 2. SQL …
Availability Databases
Availability Replicas
- Each availability group defines a set of two or more failover partners known as availability replicas. Availability replicasare components of the availability group. Each availability replica hosts a copy of the availability databases in the availability group. For a given availability group, the availability replicas must be hosted by separate instances of SQL Server residing on different nodes of a W…
Availability Modes
- The availability mode is a property of each availability replica. The availability mode determines whether the primary replica waits to commit transactions on a database until a given secondary replica has written the transaction log records to disk (hardened the log). Always On availability groups supports two availability modes-asynchronous-commi...
Types of Failover
- Within the context of a session between the primary replica and a secondary replica, the primary and secondary roles are potentially interchangeable in a process known as failover. During a failover, the target secondary replica transitions to the primary role, becoming the new primary replica. The new primary replica brings its databases online as the primary databases, and clien…
Client Connections
- You can provide client connectivity to the primary replica of a given availability group by creating an availability group listener. An availability group listenerprovides a set of resources that is attached to a given availability group to direct client connections to the appropriate availability replica. An availability group listener is associated with a unique DNS name that serves as a virt…
Active Secondary Replicas
- Always On availability groups supports active secondary replicas. Active secondary capabilities include support for: 1. Performing backup operations on secondary replicasThe secondary replicas support performing log backups and copy-only backups of a full database, file, or filegroup. You can configure the availability group to specify a preference for where backups sho…
Session-Timeout Period
- The session-timeout period is an availability-replica property that determines how long connection with another availability replica can remain inactive before the connection is closed. The primary and secondary replicas ping each other to signal that they're still active. Receiving a ping from the other replica during the timeout period indicates that the connection is still open, and that the ser…
Automatic Page Repair
- Each availability replica tries to automatically recover from corrupted pages on a local database by resolving certain types of errors that prevent reading a data page. If a secondary replica cannot read a page, the replica requests a fresh copy of the page from the primary replica. If the primary replica cannot read a page, the replica broadcasts a request for a fresh copy to all the secondar…
Related Content
- Blogs:SQL Server Support Blog - High AvailabilitySQL Server Blog - SQL Server Always OnArchive: SQL Server Always On Team Blogs: The official SQL Server Always On Team BlogArchive: CSS SQL Server E...
- Whitepapers:Microsoft SQL Server Always On Solutions Guide for High Availability and Disaster RecoveryMicrosoft White Papers for SQL Server 2012
See Also