Tuesday, November 19, 2019

Data Platform Tips 3 - Auto-failover groups

Failover group is a group of databases managed by a single Database server or within a single managed instance that can failover as a group to another region in disaster situations. Supports both  Automatic and Manual failover,

Note: Name of the failover group must be globally unique. (.database.windows.net)

Adding a single database to failover groups

a) Create new resource group named "failover-group"




















b) Create a new SQL Database named "failover-group-db1" and a SQL Server named "failover-group-server1" in 'Australia East" region.















































c) Navigate to the "failover-group-db1" and click on Failover Groups and create a failover group name as "fog-failover-group"








d) Create a secondary server named "failover-group-db-server2" in "Southeast Asia" region and add "failover-group-db1" database to the failover group.












Initiating a Manual Failover using Azure Portal


a) Navigate to the "fog-failover-group" under "fileover-group-server-1" and notice that the "failover-group-db-server1" has the primary role and "failover-group-db-server2" has the secondary role.













b) Initiate the failover by clicking the "Failover" button and once the failover is complete, "failover-group-db-server2" has the primary role and "failover-group-db-server1" has the primary role.



Monday, November 18, 2019

Data Platform Tips 2 - Active geo-replication for Azure SQL Database


active geo-replicationActive Geo-replication is a business continuity feature on Azure SQL Database for quick disaster recovery in case of regional disasters. With geo-replication enabled, it creates readable secondary in the same or different region data center. It supports up to 4 secondaries in the same or different region and can be used for read only query access.

Supports only manual failover.

Active Geo-replication uses Always-On technology to asynchronously replicate committed transactions on the primary database to a secondary database using snapshot isolation.

To guarantee that the changes in primary is replicated in the secondary before initiating a failover, the application can call the stored procedure "sp_wait_for_database_copy_sync" to force the synchronisation from Primary to Secondaries. Also use the stored procedure "sys.dm_geo_replication_link_status" to check the replication status.

Initiate geo-replication using Azure Portal

a) Create a new resource group named "active-geo-replication".





b) Create a new Azure SQL Database




c) Select the newly created database "active-geo-replication-db1" and click on geo-replication.












d) As you can see below the secondary database for active geo-replication hasn't been configured and let us configure it.



e) Select the secondary database region as "Southeast Asia" and configure the secondary database and server


























f) Once the secondary replica database is created, you can see the replica database created in the "Southeast Asia" region.

i) The secondary replica is a read only replica as shown below.

Initiating Failover using Azure Portal


a) Initiate a failover by right clicking on the secondary replica and clicking on "Forced failover" and click ok to continue. Note: With forced failover, you may encounter data loss. To avoid data loss, the data synchronisation needs to be completed before initiating the failover using "sp_wait_for_database_copy_sync"

b) Once the failover the complete, you can notice the database in "Southeast Asia" region as primary and secondaries in "Australia East" region becomes readonly.


c) The failover is now complete.

Sunday, November 17, 2019

Data Platform Tips 1 - Data redundancy in Azure Storage


When we create a storage account on Azure, one of the following redundancy options can be chosen.
  • Locally redundant storage (LRS)
  • Zone redundant storage (ZRS)
  • Geo redundant storage (GRS)
  • Read Access Geo redundant storage (RA-GRS)
  • Geo-zone-redundant storage (GZRS)
  • Read-Access geo-zone-redundant storage (RA-GZRS)

Features
LRS
ZRS
GRS
RA-GRS
GZRS
RA-GZRS
Data Replication
Replicates data 3 times within same data center
Replicates data 3 storage clusters within same region physically separated from others
Replicates data to secondary region
Read-only access to secondary region in addition to geo-replication across 2 regions
Replicates data across 3 availability zones in primary region along with replicating in secondary region
Data can be read from both Primary and Secondary  endpoints.
Durability
99.999999999% (11 nines)
99.9999999999% (12 9's)
99.99999999999999% (16 9's)
99.99999999999999% (16 9's)
99.99999999999999% (16 9's)
99.99999999999999% (16 9's)
Supported Storage account types
GPv2, GPv1, Blob
GPv2
GPv2, GPv1, Blob
GPv2, GPv1, Blob
GPv2
GPv2

Wednesday, November 06, 2019

SQL Server 2019 is now GA

SQL Server 2019 is now generally available and announced at Microsoft Ignite 2019 on Day 1. SQL Server 2019 is an unified platform for enterprises to meet their business needs.

SQL Server 2019 in addition supports Big Data Clusters, Data Virtualization, Data Marts and Enterprise Data Lake.


More information - https://cloudblogs.microsoft.com/sqlserver/2019/11/04/sql-server-2019-is-now-generally-available/

Download SQL Server 2019 - https://www.microsoft.com/en-us/evalcenter/evaluate-sql-server-2019

What's new - https://docs.microsoft.com/en-us/sql/sql-server/what-s-new-in-sql-server-ver15?view=sql-server-ver15

Download - Introducing SQL Server 2019 e-book

Tuesday, November 05, 2019

MS Ignite 2019 - Day 1 - Key Announcements

Day 1 Keynote



Enables customers to have a central, unified, and self-service approach to manage their Windows and Linux Servers, Kubernetes clusters, and Azure data services wherever they are. Azure Arc also extends adoption of cloud practices like DevOps and Azure security across on-premises, multi-cloud and edge.


Azure Synapse Analytics - Single Cloud Analytics to bridge Data Lakes and Data Warehouses

Organisations currently need to have Data Lakes to store raw data and get valuable insights from the data in a timely fashion and Data Warehouses to facilitate on-going and historical insights over the data. Both these systems are critical for any organisation. Azure Synapse Analytics brings both Data Lakes and Data Warehouses together to provide Enterprise Analytics.


Empower Developer Velocity - Announcing Visual Studio Online - Web version of Visual Studio

Visual Studio Online is a cloud powered development environment accessible from anywhere and any device. Visual Studio Online has a browser-based editor with support for Git repositories, extensions, and a built-in command line interface so you can edit, run, and debug  your applications from any device.

Azure AI for companies of all sizes to solve business problems

Microsoft has announced key enhancements in Machine Learning capabilities including ML Designer, Automated Machine Learning enhancements and built-in Notebooks to support Data Scientists and Developers at all skill levels. 

Personalizer, the Cognitive Service is the first industry's AI service that is based on reinforcement learning. 

A new Bot Framework Composer helps simplify the creation of bots through a graphical user interface.

Data Driven culture to accelerate Innovation

Azure SQL Edge (Preview) by Microsoft Azure is a resource-light, edge-optimised data engine with built-in AI. Azure SQL Database Edge brings data streaming, storage, full time series support, and AI capabilities to edge computing scenarios.





Wednesday, July 10, 2019

Cognitive Services and Authentication using multi-service Subscription Key

Any request to Cognitive Services needs to be authenticated. For using multiple Cognitive Services like Computer Vision, Text Analytics, you can use still use a single subscription key to authenticate your requests.

Note: QnA Maker, Speech Services, Custom Vision, and Anomaly Detector services don’t support multi-support Subscription Key.















Pre-requisites
  • Azure Subscription
Steps
1. Log on to the Azure Portal
2. Create a new resource of type “Cognitive Service” from the marketplace.

















3. Type the name of the resource, subscription, location, pricing tier and resourcing group. Also pay attention to the online services terms.















4. Once the resource is created, note down the endpoint and access keys. The same access key can be used to authenticate any Cognitive Services like Custom Vision, Text Analytics etc.
























Download code: https://github.com/shantha05/CognitiveServices (CognitiveServicesDemo project)
Technorati Tags:


Tuesday, July 09, 2019

Cognitive Services and Authentication using Single Subscription Key

Any request to Cognitive Services needs to be authenticated. For using single Cognitive Service like Computer Vision or Custom Vision you can use separate subscription key for each specific service to authenticate your requests.
Pre-requisites
  • Azure Subscription
Steps
1. Log on to the Azure Portal
2. Create a new resource “Computer Vision” from the marketplace.















3. Type a name for the resource, subscription, location, pricing tier and resourcing group.




















4. Once the resource is created, note down the endpoint and access keys. The access key can be used only to authenticate to “Computer Vision” resource and cannot be used to authenticate other Cognitive Services like Custom Vision, Text Analytics etc.


























Download code: https://github.com/shantha05/CognitiveServices
Technorati Tags: Cognitive Services