High Availability

[Video] SQL Server Always On Availability Groups 101

Last Updated August 21, 2024

I got a few closely related Availability Groups questions at https://pollgab.com/room/brento and decided to do a half-hour introduction to AGs: Here’s what we covered: 00:00 Start 00:24 Paul Hunter: My company decided to move to AZURE. The person in charge of moving the SQL Server decided to put up an AG (I voiced my concerns…

Adding Managed Instances to SQL Server Distributed Availability Groups

Last Updated June 20, 2021

Brent Ozar

Always On Availability Groups, Managed Instances

SQL Server Always On Availability Groups help you build a more highly available database server by spanning your database across two or more SQL Server instances. When the primary goes down, the secondary can take over. You can also scale out reads to the secondary servers. Distributed Availability Groups take this a step further and…

DBA Training Plan 21: Building a New SQL Server

Last Updated July 31, 2024

Brent Ozar

DBA Training Plan, High Availability

I have a secret setup checklist. Oh sure, our free First Responder Kit has a SQL Server setup checklist that walks you through a few things you need to do before you install, plus a few things to do immediately afterwards. That’s good. It’s actually pretty darned good. But it’s not the secret checklist. Gather round and cover your…

20 Questions to Ask About Your Availability Group Design

Last Updated December 26, 2018

Brent Ozar

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

Erik Darling

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…

How to Test Disaster Recovery Before You Go Live

Last Updated July 2, 2018

Brent Ozar

High Availability

When I build a server, success means not touching the server again for 2-3 years. I already have enough crappy, unreliable servers that fall over when someone walks past. I only wanna build good, permanent stuff going forward. So when I build disaster recovery for something, I want to test it 3 ways: Planned failover…

Training Week: Announcing Edwin’s New Class on Failover Clustered Instances

Last Updated April 11, 2018

Brent Ozar

Clustering, Company News

This week, we’ve got a bunch of announcements about new training classes. Next up, Edwin Sarmiento: his 3-day Always On Availability Group class has been getting great reviews: “This class is fantastic. There is no filler, and no needless repetition, so be prepared to pay attention the entire duration. Edwin clearly is very passionate about…

So You Want a Cheap Disaster Plan

Last Updated November 22, 2017

Tara Kizer

Cloud Computing, Log Shipping

There’s a lot that goes into a Disaster Recovery plan. One of them is offsite backups. There are some businesses that don’t have backups going offsite, let alone a Disaster Recovery plan. This conversation has taken place more than I thought it would. Me: Do you have any HA or DR features in place? Them:…

An Expensive Reason To Avoid AGs In Azure

Last Updated August 27, 2017

Erik Darling

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…

sp_AllNightLog: Creating Jobs Like I’m The President

Last Updated August 11, 2017

Erik Darling

Backup and Recovery, Clients and Case Studies, ISV and SaaS Database Design, kCura Relativity, Log Shipping, SQL Server

Look, we need these things The setup for sp_AllNightLog creates jobs for four separate activities 1 job to poll for new databases to back up (primary) 1 job to poll for new databases to restore (secondary) 10 jobs to poll for backups to take (primary) 10 jobs to poll for restores to… whatever (secondary) And,…

sp_AllNightLog: Poll Vaulting

Last Updated July 12, 2017

Erik Darling

Backup and Recovery, Clients and Case Studies, ISV and SaaS Database Design, kCura Relativity, Log Shipping, SQL Server

Carry on It turns out that the only thing harder than checking for new databases restored to a SQL Server, is checking a folder for a backup of a database that doesn’t exist on another SQL Server. These are both part of what sp_AllNightLog has to do. The other components, which use workers and a…

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

Last Updated June 10, 2017

Brent Ozar

Always On Availability Groups

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

Erik Darling

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 a SQL Server Disaster Recovery Plan with Google Compute Engine

Last Updated March 17, 2017

Tara Kizer

Google Compute Engine, High Availability, Log Shipping, Processes and Practices

You’re a systems administrator or database administrator who wants to protect your production SQL Server. However, you don’t have a separate data center or another colo site. Learn about what we call Log Shipping 2.0 You’re looking for instructions on: How to copy your SQL Server databases to Google Cloud Storage How to spin up…

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

Last Updated March 17, 2017

Brent Ozar

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

Brent Ozar

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

Brent Ozar

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

Brent Ozar

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…

The Cost of Adding a Reporting Server

Last Updated February 13, 2017

Brent Ozar

Architecture, Licensing, Log Shipping, SQL Server

“We’d like to offload our reporting queries to a separate SQL Server.” The first costs are fairly obvious. Hardware and storage – even if you’re running it in a virtual machine, you need to account for the costs of say, 4 cores and 32GB RAM. Not only will you need storage for the databases, but…

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,…