— 3 min read

Quick introduction

My employers presented me with a challenge this week. The task was not difficult in the end but to me it was an untried concept involving MySQL.

I have never been a fan of MySQL and generally turn my nose at the thought of using it, let alone replicating it etc.

The task in question? Master -> Master -> Slave -> Slave replication.

From this point forward I will expect you to have MySQL installed and set-up as normal.

  • Master 1 will be known as Master 1 and Slave 2 with IP
  • Master 2 will be known as Master 2 and Slave 1 with IP
  • Slave 1 will be known as Slave 3 with IP
  • and Slave 2 will be known as Slave 4 with IP

Master 1

Modify your MySQL config file, usually named …

 — 3 min read

During a seemingly normal work day a colleague pointed out a problem to me and asked if I had any solution.

The problem was that they were trying to use InfoBright (https://www.infobright.com/) for some data crunching, export the data to CSV and then import in to MySQL. My first idea was to output the data from InfoBright as SQL and pipe it directly in to MySQL, this turned out to not be possible as the version of IB they were using only supported output as CSV.

This in itself wasn’t a problem, the problem lay with the fact that IB would only output the file with 0660 permissions, and although both IB and MySQL ran as user mysql and group mysql, MySQL itself flat out refused to import the CSV file unless it was world readable (0664), which was slightly annoying.

If the CSV didn’t …