When people buy my virtualization training video, one of the followup questions I get most often via email is, "Can I build SQL Server clusters in VMware and Hyper-V?"
In theory, yes. Microsoft's knowledge base article on SQL Server virtualization support says they'll support you as long as you're using configurations listed in the Server Virtualization Validation Program (SVVP).
I recently finished helping the StackExchange team migrate their SQL Server 2008 infrastructure to SQL Server 2012. These servers power StackOverflow, DBA.StackExchange.com, the new AskPatents partnership with the US Patent and Trademark Office, and hundreds of other Q&A sites that together form one of the biggest web site networks. It's one of the most visible…
Think fast! When it's time to do a manual failover with SQL Server 2012 AlwaysOn Availability Groups, we need to make a few decisions and perform a few tasks as quickly as possible to get the business back up and running. Here's what you need to consider ahead of time so you can stay calm, cool, and collected - even if you have to trust someone else to do this work.
If you've ever wanted to use the cloud for a DR site, there's good news: as of this week you can use AlwaysOn Availability Groups and set up an asynchronous replica of your data into Amazon Web Services (AWS). If you're already in the cloud, or if you were holding off, this means that you…
If you're using SQL Server 2012's hot new AlwaysOn Availability Groups feature, your databases will go offline when your network connection does - even if you're using asynchronous replication.
This is not a bug. This is working as designed - and it's important to understand the underlying concepts.
Remember that weirdo in high school who had no social skills? Couldn't get a date, worked at the fast food joint as a fry cook, face covered with zits - you know the one. Okay, actually, it was us. Anyway, the point is, we got our act together, didn't we? So did Windows Failover Clustering. …
Many companies are investigating a move into cloud hosting. With the recent release of SQL Server 2012, these very same companies are also looking at a migration to SQL Server 2012 to take advantage of readable secondaries. Combining Amazon Web Services and SQL Server 2012 seems like a perfect match. Unfortunately, there are some gotchas,…
Professions go through phases. Some skills are highly valued for a while, then go out of fashion. Just like leg warmers and skinny jeans, some skills come back into style when you least expect it. Database Administrators Started Out in the Server Room In the early days, most database administrators started out by racking servers.…
With SQL Server 2012's new AlwaysOn Availability Groups, we have the ability to run queries, backups, and even DBCCs on database replicas. But should we? Paul Randal (Blog - @PaulRandal) covered this issue in today's SQLskills Insider newsletter, and he says: "It’s not checking the I/O subsystem of the log shipping primary database – only…
The options for high availability can get confusing. I was lucky enough to begin working with SQL Server clusters early in my career, but many people have a hard time finding simple information on what a cluster does and the most common gotchas when planning a cluster. Today, I’ll tell you what clusters are, what they’re…
Connection strings - boring topic, right? Well, it turns out there's a few things that can save your behind.
Tip 1: Build your application with 3 connection strings.
If you want to scale, write your application from the start with 3 different connection strings:
Writes and real-time reads
Reads that can tolerate data older than 15 seconds (no writes allowed with this connection string)
Reads that can tolerate data several hours old (like reports, and no writes allowed with this string)
The cloud is robust and reliable. The cloud solves all of our scaling needs. The cloud makes my poop smell like roses. While all of these statements are theoretically true it takes some effort to make them true in reality, especially when a database is involved. Who Is Deploying SQL Server in EC2? A question…
Before we get started, we need to talk about something. I'm going to be using the C word - that's right, Clustering. Deep, calming breaths. Relax. We can do this, you and me. This isn't the old-school clustering with shared disks, heartbeat networks, and hardware compatibility lists. This is just another feature you're going to…
In part 1 of this post, I covered how SQL Server handles scaling up. We talked about how quickly it becomes expensive to add more CPU power, memory, and storage throughput to our database servers. Today, we're going to focus on a different way to scale. When most folks talk about scaling out SQL Server,…
SQL Server 2012 brings huge improvements for scaling out and high availability. To put these changes into perspective, let's take a trip down memory road first and look at the history of database mirroring. SQL Server 2005 first introduced mirroring, although it wasn't fully supported until a service pack. In many ways, mirroring beat the…
Want to know how much it'll cost to back up your database transaction logs to Amazon S3? I'll show you with a snippet of T-SQL. Note the parameters at the top for retention periods. The defaults assume one full backup weekly. DBAs would normally want to do full backups more often, but when you're paying…
Are you using any of these technologies as a method of database protection?
Database mirroring (keeping two database servers synchronized with the same data via SQL 2005/2008)
Replication (copying records between databases)
Log shipping (copying log files to another server and restoring them immediately)
SAN-based mirroring (storing two copies of your database on two different sets of disks)
