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David Barbarin

SQL Server 2017 AlwaysOn AGs and new read-scale architectures

By | Database Administration & Monitoring | No Comments

As you probably know Microsoft announced an official name for SQL Server vNext during the last Microsoft Data Amp event on April 19 2017. It becomes officially SQL Serve 2017. In my first blog post, I wrote about SQL Server on Linux and the introduction of availability groups features. At this moment the SQL Server release version was CTP 1.3. As a reminder, with previous CTP releases, listeners were unusable because they did not persist when…

 
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David Barbarin

Speaking at the next SQL Nexus at Copenhagen 2017

By | Database Administration & Monitoring | No Comments

On May 2nd, I will have the chance to speak during the next SQL Nexus event in Copenhagen (1 -3 may) about SQL Server 2016 and availability groups and if I have enough time, you will see what is coming with the SQL Server vNext. This is also a good opportunity to attend to other sessions held by well-known people in the industry like David Klee, Edwin M Sarmiento, Wolfgang Strasser and Uwe Ricken  to name a…

 
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David Barbarin

Introducing AlwaysOn availability groups on Linux

By | Database Administration & Monitoring | No Comments

A couple of days ago, Microsoft has rolled out the SQL Server vNext CTP 1.3 which includes very nice features and the one that interested me in the supportability of AlwaysOn availability groups on Linux. That is definitely a good news because we may benefit from new ways of architecting high-availability. There are a lot of new cool enhancements, which we’ll try to study when writing new blog posts. In this first blog, let’s learn…

 
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David Barbarin

Dealing with WSFC 2016 quarantine state and availability groups

By | Database Administration & Monitoring, Operation systems | No Comments

I was playing with my lab environment which includes Windows 2016 and SQL Server 2016 and I noticed an interesting scenario while testing cluster node failures. After simulating some network outage scenarios, I was not able to bring back my cluster node online immediately by using traditional way. A quick look at the cluster manager led me to notice something new: A quarantined state value … interesting! But what does it mean exactly? In respect…

 
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David Barbarin

Migrating your existing availability group infrastructure to 2016

By | Database Administration & Monitoring | No Comments

Have you already a plan to migrate your old SQL Server 2012 availability group infrastructure to windows 2016 and SQL Server 2016? In a previous post, I talked about distributed availability groups and cross-cluster migration scenarios but this time the game is not the same because we want to achieve an in-place upgrade of the existing AG infrastructure. This question will probably be a concern the next year and if we take a closer look…

 
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David Barbarin

SQL Server 2016: distributed availability groups and cascaded replicas

By | Database Administration & Monitoring | No Comments

During the last MVP summit, we had some interesting discussions about availability groups with the SQL Server team and I remember someone asked for managing scenarios like Oracle cascaded destinations and the good news is that SQL Server 2016 already addresses this kind of scenario with distributed availability groups. For example, let’s say you have to manage heavily reporting activity on your application and a solution would be to offload this activity across several secondary…

 
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David Barbarin

SQL Server AlwaysOn availability groups and statistic issues on secondaries

By | Database Administration & Monitoring | No Comments

I would like to share with you an interesting issue you may face while using SQL Server AlwaysOn availability groups and secondary read-only replicas. For those who use secondary read-only replicas as reporting servers, keep reading this blog post because it is about update statistics behavior on the secondary replicas and as you may know cardinality estimation accuracy is an important part of the queries performance in this case. So a couple of days ago,…

 
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David Barbarin

SQL Server 2016: Distributed availability groups and Cross Cluster migration

By | Database Administration & Monitoring | No Comments

How to migrate an environment that includes availability groups from one Windows Failover Cluster to another one? This scenario is definitely uncommon and requires a good preparation. How to achieve this task depends mainly of your context. Indeed, we may use a plenty of scenarios according to the architecture in-place as well as the customer constraints in terms of maximum downtime allowed for example. Among all possible scenarios, there is a process called “cross-cluster migration…

 
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David Barbarin

SQLSaturday #546 Porto – Troubleshooting scenarios with availability groups

By | Database management, Technology Survey | No Comments

J-1 before the next SQL Saturday 2016 in Portugal. I usually promote this event in France but this time this is for SQL Server Portuguese community. I will have the chance to talk about SQL Server AlwaysOn and troubleshooting scenarios. It will be also a good opportunity to meet portuguese people like Niko Neugebauer (@NikoNeugebauer), André Batista (@klunkySQL) and many others. Moreover, Porto is definitely a beautiful city and a good way to finish the summer…

 
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David Barbarin

SQL Server 2016 : Basic availability groups may fit to your HA needs

By | Database Administration & Monitoring | No Comments

In this blog let’s talk about SQL Server and availability groups in standard Edition. I had some customer questions about existing limitations and this is a good opportunity to review them on this blog post. First of all, let’s say that Microsoft has already documented the restrictions here and from my side, I already written a blog post on the subject at the time of the CTP version of SQL Server 2016. In the meantime,…

 
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