Infrastructure at your Service

Tag

High availability Archives - Page 7 of 9 - Blog dbi services

Microsoft Team

SQL Server AlwaysOn : readable secondary replicas and index rebuild online vs offline

By | Database Administration & Monitoring | 4 Comments

A couple of weeks ago, I was involved in a discussion on the French forum developpez.com about SQL Server AlwaysOn and availability groups, index strategies and the impact on the readable secondary replicas. During this discussion, one of the forum member stated that rebuilding an index online had less impact than rebuilding an index offline on a readable secondary replica but I disagree with this affirmative. Is it really true? Let’s verify in this blog…

Read More
Microsoft Team

SQL Server 2016 : availability groups and the new ssis_monitor role for SSIDBB catalog

By | Database Administration & Monitoring | No Comments

During my investigation about the new AlwaysOn features, I wrote a blog post about the new SSISDB support for AlwaysOn. You can find it here: > SQL Server 2016 : availability groups and the new SSISDB support Just as a reminder, for those who have dealt with the SSISDB catalog in the previous version, some extra works were mandatory to be “AlwaysOn” compliant. Fortunately, the new version of SSIDB catalog will make easier the DBA…

Read More
Microsoft Team

SQL Server AlwaysOn: number of databases and the hadr worker pool

By | Database Administration & Monitoring | One Comment

Often, when I’m in charge to implement an SQL Server AlwaysOn infrastructure with availability groups, customers ask me if it exists some best practices and recommendations about the maximum number of databases in an availability group planning. In fact, we have to keep in mind the relation between databases and the SQL Server worker pool in this architecture. Remember that the SQL Server AlwaysOn and availability group feature is an extension of the SQL Server…

Read More
Daniel Westermann

ACFS 12.1.0.2 on Oracle Linux 7.1

By | Database Administration & Monitoring | 2 Comments

Recently we wanted to create an ACFS filesystem on a brand new 12.1.0.2 GI installation on Oracle Linux 7.1. According to the documentation this should not be an issue as “Oracle Linux 7 with the Unbreakable Enterprise kernel: 3.8.13-33.el7uek.x86_64 or later” is supported. The “or later” is the important point. In our case: uname -a Linux racp1vm1 3.8.13-55.1.6.el7uek.x86_64 #2 SMP Wed Feb 11 14:18:22 PST 2015 x86_64 x86_64 x86_64 GNU/Linux   Should be fine as…

Read More
Microsoft Team

SQL Server 2016 : availability groups and the new SSISDB support

By | Hardware & Storage | 11 Comments

This blog post is focused on the new supportability of SSIDB catalog on AlwaysOn architecture. Others studies are available here: New database issue level detection for automatic failover Potential features in standard edition Automatic failover enhancements New load balancing features with read-only replicas New clustered columnstore index support A couple of weeks ago, I was involved in an SSIS infrastructure project with SQL Server 2014. As you know, the SSIS architecture has fundamentally changed since…

Read More
Microsoft Team

SQL Server 2016 : availability groups and load balancing features

By | Hardware & Storage | 8 Comments

Let’s continue with this third post about SQL Server AlwaysOn and availability groups. Others studies are available here: New database issue level detection for automatic failover Potential features in standard edition Automatic failover enhancements This time I’ll talk about read-only secondaries and the new load-balancing support that will be introduced by SQL Server 2016. First of all, SQL Server 2014 improved the read-only secondary availability by solving the issue related to secondary accessibility when the…

Read More
Microsoft Team

SQL Server 2016 : availability groups and automatic failover enhancements

By | Hardware & Storage | 3 Comments

Let’s continue with this study of the new availability group enhancements. Others studies are available here: New database issue level detection for automatic failover Potential features in standard edition This time we’ll talk about the possibility to enrol a third replica for automatic failover. It implies of course to configure synchronous replication between the 2 pairs of replicas and this is at the cost of degrading the overall performance. But it seems that in this…

Read More
Microsoft Team

SQL Server 2016 : availability groups and the new potential support for standard edition

By | Hardware & Storage | No Comments

In my first blog about availability groups with SQL Server 2016, I talked quickly about the new interesting option: DB_FAILOVER. In this blog post, I will continue by introducing the new potential support of availability groups in a standard edition (based on the last Microsoft Ignit news). Yes, this sounds a great news because it will increase the scope of possible customers but bear in mind that it concerns potentially the standard edition (not in…

Read More
Microsoft Team

Weird issue with sys.fn_hadr_backup_is_preferred_replica() function

By | Hardware & Storage | No Comments

A couple of days ago, I faced a weird backup issue with SQL Server AlwaysOn and availability groups at one of my customer (thank to him to point out this issue 🙂 ). After installing our DMK tool (Database Management Kit) about database maintenance for AlwaysOn, my customer noticed that their databases have not backed up. Ouch … what’s going on? I never ran into this issue before… Do the problem comes from our tool?…

Read More
Microsoft Team

Windows Cluster vNext and cloud witness

By | Operation systems | No Comments

The next version of Windows will provide some interesting features about WFSC architectures. One of them is the new quorum type: “Node majority and cloud witness” which will solve many cases where a third datacenter is mandatory and missing to achieve a truly resilient quorum. Let’s imagine the following scenario that may concern the implementation of either an SQL Server availability group or a SQL Server FCI. Let’s say you have to implement a geo-cluster…

Read More