Building a Database Menagerie...

• This is a work-in-progress: last change: 01/14/2021

Wouldn't it be nice to have a database that just runs and runs, no matter what? Let's create a geographically dispersible database, using cheap tiny computers - a menagerie of different PCs.

Why would I want to do this?  Well, databases are great, but if your server fails your database is usually stuck, and it's a mad scramble to fix it. It sucks. And getting it going again is always a mess.

What if we could have a database that just keeps running, even if one (or more) servers fail; what if they could all run on cheap hardware or in the cloud, and if they could be geographically spread around so a power or system failure in one is not a failure of the whole database, then we all win.

The database software choice

My choice of database software was a crucial part of this decision.

• I needed something that could run on a variety of machines (and/or in the cloud).  
• I like the simplicity of NoSQL, which scales very well.
• But I kept coming back to SQL and relational databases - better transactions, better consistency, more transactional features, etc.
• But most SQL system do not scale well, or scale only with add-ons and complex sharding techniques.  
• I wanted software that scaled easily, and could run on more than one cloud provider at once.
• I needed something that could automatically survive failure - both hardware and software failures. And I wanted it able to automatically recover from that failure once fixed.
• It needed it to be easy-to-deploy and maintain (no maintenance is even better).
• I needed something straddling the line between a relational and a NoSQL database - was I crazy?
• This is really a religious discussion, and worthy of many articles.  :-)

In the end, I chose the awesome CockroachDB.  This easily scales to hundreds of servers, uses standard PCs and/or mega-core monsters, uses standard SQL, handles failure and recovery automatically, distributes workload for faster results, and has a free/open-source version. And it has worked extremely well in my setup.  Winner Winner Chicken Dinner.

These articles

I went through a number of trials over a year to get to the end result, so I needed to boil it all down.  We'll start with a blank computer and go from there to a working database cluster.

This will be a series of short articles, with this one the starting point to the details.  In other words, it's the...

Table of Contents

1. Hardware Choices (with price & speed comparisons)
2. Hardware Setup
3. Operating System Setup
4. Supporting Software Setup
5. Database Software Setup
6. Now what?

Let me know what you think!