Always On Availability Groups

Questions about the overall project: What are your RPO and RTO goals? Are there financial penalties if we miss the goals? (Like contracts, refunds to customers, etc) Does this app have regularly scheduled maintenance windows, or is it 24/7? What’s the ballpark size of the data today? In 3 years? Questions about the team: How…

Have Availability Groups Gotten Easier Lately?

Last Updated December 3, 2018

Always On Availability Groups, High Availability, SQL Server

Easy Lover I don’t blog a lot about AGs. If we’re being honest (and I do try to be honest with you, dear reader), I just like performance tuning topics way more. When new features get announced for AGs, some of you may ooh and aah, but not me. I Make A Face I don’t…

[Video] Installing SQL Server Updates in an Availability Group, and Save 50% on Training

Last Updated July 2, 2018

Always On Availability Groups, Videos

This week, we’re sharing Instant Replay videos from our training classes. Today’s Instant Replay is Edwin Sarmiento talking about how he approaches applying service packs and cumulative updates on Always On Availability Groups: That video is part of the Instant Replay recordings of Edwin’s extensive live 3-day Senior DBA’s Guide to Always On Availability Groups.…

An Expensive Reason To Avoid AGs In Azure

Last Updated August 27, 2017

Always On Availability Groups, Backup and Recovery, CHECKDB and Corruption, Cloud Computing, High Availability, Microsoft Azure, SQL Server

Cash Rules Most people, when they get through paying for Azure, and SQL Server Enterprise Licensing, are left with a hole in their wallet that could only be filled with something that says “Bugatti”, and has a speedometer with an infinity sign at the end. Recently, while working with a client, I found out that…

New Class: Always On Availability Groups: The Senior DBA’s Field Guide

Last Updated June 10, 2017

Availability Groups are all the rage right now, especially since they’re included with SQL Server 2016 Standard Edition. Our Availability Groups blog post category is one of the most popular on the site, and in my 4-day Senior DBA class, people have always been asking for more in-depth coverage of clustering and AGs. Let’s get together for a…

Direct Seeding: I’ve Got A Wizard And You Don’t

Last Updated May 26, 2017

Always On Availability Groups, High Availability

A commenter commented That the “New AG Wizard” in SSMS 2017 had surfaced the Direct Seeding mode for AGs. I was pretty psyched about this because I think it’s a great feature addition to AGs that can solve for a pretty big hump that people run into when they create databases regularly. It used to…

New White Paper: How to Build an Always On Availability Group in Google Compute Engine

Last Updated March 17, 2017

Always On Availability Groups, Google Compute Engine, SQL Server

You’re a database administrator, Windows admin, or developer. You want to build a Microsoft SQL Server environment that’s highly available, and you’ve chosen to use Always On Availability Groups. Our newest white paper – download In this white paper we built with Google, we’ll show you: How to build your first Availability Group in Google…

Always On Availability Groups Now Supported in Google Compute Engine

Last Updated February 9, 2017

Always On Availability Groups, Cloud Computing, Google Compute Engine

I’m excited to finally be able to talk about something Erik, Tara, and I have been working on for the last few months. Here in the SQL Server community, when I mention cloud, you probably think of two companies: Microsoft and Amazon. We’ve been blogging about SQL in AWS for years, and Microsoft throws a…

When Always On Isn’t: Handling Outages in Your Application

Last Updated February 9, 2017

Always On Availability Groups, Stack Overflow

Today’s brief Stack Overflow outage reminded me of something I’ve always wanted to blog about: Stack Overflow is in limp-home mode There’s a gray bar across the top that says, “This site is currently in read-only mode; we’ll return with full functionality soon.” That’s not a hidden feature of Always On Availability Groups. Rather, it’s a…

Availability Groups: More Planned Downtime for Less Unplanned Downtime

Last Updated September 21, 2017

Always On Availability Groups, Breaking News, SQL Server

I often hear companies say, “We can never ever go down, so we’d like to implement Always On Availability Groups.” Let’s say on January 1, 2016, you rolled out a new Availability Group on SQL Server 2014. It’s the most current version available at the time, and you deploy Service Pack 1, Cumulative Update 4 (released…

Asynchronous Database Mirroring vs. Asynchronous Availability Groups

Last Updated February 9, 2017

Tara Kizer

Always On Availability Groups, Database Mirroring, SQL Server

When Database Mirroring came out in SQL Server 2005 Service Pack 1, we quickly dropped Log Shipping as our Disaster Recovery solution. Log Shipping is a good feature, but I can failover with Asynchronous Database Mirroring faster than I can with Log Shipping. When Always On Availability Groups (AG) came out in SQL Server 2012,…

Updated High Availability and Disaster Recovery Planning Worksheet

Last Updated February 23, 2021

Always On Availability Groups, Backup and Recovery, Clustering, SQL Server

One of the most popular things in our First Responder Kit is our HA/DR planning worksheet. Here’s page one: Page 1 – how our servers are doing now, versus what the business wants In the past, we had three columns on this worksheet – HA, DR, and Oops Deletes. In this new version, we changed “Oops”…

Availability Group Direct Seeding: Mind Your Backup Jobs

Last Updated February 9, 2017

Always On Availability Groups, Backup and Recovery, SQL Server

I’ll get right to the point While you’re Direct Seeding, you have to be careful with any other full or differential backup jobs running on the server. This is an artifact of the Direct Seeding process, but it’s one you should be aware of up front. In the screencap below, courtesy of sp_whoisactive there’s a…

Availability Group Direct Seeding: TDE’s Frenemy

Last Updated February 9, 2017

From the Mailbag In another post I did on Direct Seeding, reader Bryan Aubuchon asked if it plays nicely with TDE. I’ll be honest with you, TDE is one of the last things I test interoperability with. It’s annoying that it breaks Instant File Initialization, and mucks up backup compression. But I totally get the…

Availability Group Direct Seeding: Extended Events and DMVs

Last Updated February 9, 2017

As of this writing, this is all undocumented I’m super interested in this feature, so that won’t deter me too much. There have been a number of questions since Availability Groups became a thing about how to automate adding new databases. All of the solutions were kind of awkward scripts to backup, restore, join, blah…

Availability Group Direct Seeding: How to fix a database that won’t sync

Last Updated February 9, 2017

This post covers two scenarios You either created a database, and the sync failed for some reason, or a database stopped syncing. Our setup focuses on one where sync breaks immediately, because whatever it’s my blog post. In order to do that, I set up a script to create a bunch of databases, hoping that…

SQL Server 2016: Availability Groups, Direct Seeding, and You.

Last Updated February 9, 2017

One of my least favorite things about Availability Groups Well, really, this goes for Mirroring and Log Shipping, too. Don’t think you’re special just because you don’t have a half dozen patches and bug fixes per CU. Hah. Showed you! Where was I? Oh yeah. I really didn’t like the backup and restore part. You…

Training Plan for a SysAdmin to Manage Availability Groups

Last Updated April 9, 2017

Kendra Little

How hard is it for a systems administrator who’s used to running SQL Server on Windows Clusters to tackle Availability Groups? Our example system administrator knows a bit of TSQL and their way around Management Studio, but is pretty new to performance tuning. Well, it might be harder than you think. First, let’s look at…

AlwaysOn AG Databases Need Bigger Log Files

Last Updated February 9, 2017