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David Barbarin

SQL Server 2017 on Linux and some log shipping scenarios

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In this blog let’s talk a little bit about the log-shipping feature from the SQL Server CTP 2.0. First of all, let’s say that as a Windows version, it is possible to create our own solution based on Linux (and cron jobs for example). You may find out different pointers on the internet that deal with this topic. But getting the built-in log-shipping feature from SQL Server presents some advantages. Indeed, this is basically the…

 
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David Barbarin

SQL Server 2017 AlwaysOn AGs and new read-scale architectures

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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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Daniel Westermann

Vertically scale your PostgreSQL infrastructure with pgpool – 3 – Adding another standby

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In the first and second post in this series we did the basic pgpool setup including the watchdog configuration and then did a simple setup for automatically failover from a PostgreSQL master instance in case it goes down for any reason. In addition we told pgpool how an old master instance can be reconfigured as a new standby instance that follows the new master. In this post we’ll add another standby instance and then teach…

 
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Daniel Westermann

Vertically scale your PostgreSQL infrastructure with pgpool – 2 – Automatic failover and reconfiguration

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In the first post of this little series we did the basic setup of pgpool and configured the watchdog. So, as of now, pgpool uses a VIP which is active on one of the pgpool nodes and failovers to the other node in case the node where the VIP currently runs on goes down for any reason. This provides the very same address for the application or clients to connect and eliminates the single point…

 
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Daniel Westermann

Vertically scale your PostgreSQL infrastructure with pgpool – 1 – Basic setup and watchdog configuration

By | Database Administration & Monitoring | No Comments

I have written some posts on how you can make your PostgreSQL deployment high available by using PostgreSQL’s streaming replication feature in the past ( 1, 2 ). The main issue you’ll have to resolve with such a setup is how the application can be made aware of a new master when a fail over happened. You could use EDB Failover Manager (1, 2, 3, 4) for that because it provides the functionality to move…

 
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David Barbarin

Speaking at the next SQL Nexus at Copenhagen 2017

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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

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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

SQL Server Failover Cluster on Linux and synchronizing uids/gids across nodes

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In my previous blog post, I talked about SQL Server on Linux and high availability. During my test, I used a NFS server to share disk resources between my cluster nodes as described in the Microsoft documentation. A couple of days ago, I decided to add a fourth node (LINUX04) to my cluster infrastructure and I expected to do this work easily. But no chance, I faced a problem I never had before on this…

 
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David Barbarin

SQL Server AlwaysOn – Distributed availability groups, read-only with round-robin capabilities

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  This blog post comes from a very interesting discussion with one of my friends about the read-only capabilities of secondary replicas in the context of distributed availability groups. Initially, distributed availability groups are designed to address D/R scenarios and some migration scenario types as well. I already discussed about of one possible migration scenario here. However, we may also take advantage of using secondary replicas as read-only in Reporting Scenarios (obviously after making an…

 
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David Barbarin

Introducing high-availability and multi-subnet scenarios with SQL Server on Linux

By | Database Administration & Monitoring | No Comments

On my first blog about SQL Server on Linux, I introduced the new high availability feature which concerns only SQL Server failover cluster instances so far. During this discovery time, I had the support of Mihaela Blendea (@MihaelaBlendea) at Microsoft to clarify some architecture aspects about this new kind of architecture. Firstly, I would like to thank her. It’s always a big pleasure to get the availability of the Microsoft team in this case. But after…

 
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