We’ve come a long way in the last year in the way we operate our sites. We’ve stabilized our applications, improved their response time, and increased their availability.
To accomplish these improvements we’ve done a series of database maintenances that varied from upgraded hardware, to new database servers, to configuration changes that required restart. In each of these operations we had one common goal: minimize the interruption to our customers.
Today we are releasing a small script that has made our lives, and our customer’s lives a whole lot better. We use this script to change the roles of our databases from replication masters to slaves, and vice versa. The fact that the script does all the steps previously performed by a human in a more timely and perfect manner is where we achieve all the gain.
Without this script we used to spend minutes accomplishing these maintenance tasks. With the script we’ve swapped databases under production load with no user noticeable interruption!
The script has lots of hard coded paths and users and other assumptions. But this is too good to keep to ourselves. We’re sharing it with you with the hope that it will improve your operations experience, and that you will contribute back changes that make it even better.