So you have been succesfully using OpenStack and now one of your volumes has started filling up. What is the best, quickest and safest way to grow the size of your volume?
Well, as always, that depends.
This is difficult in OpenStack as there is not an easy and obvious choice.
The best method is to spin up a new instance with a new volume and use the configuration management tool of your choice to make sure it is as you want it. Terminate the old instance and attach all the data volumes to the new instance.
This assumes there is no permanent data stored on the boot volume that is outside the configuration managment tool control.
Another method which is quick and safe is to perform a volume snapshot.
The process is as follows:
This sequence can be performed either through the API/commands or the dashboard.
A reason to like this method is that the original volume is maintained, it is quick and cloud-init grows the new instance filesystem to the new volume size on first boot.
The reasons not to like this method are:
Finally, there is the old fashioned methods that involves:
The way to go is: