For most open source projects it is quite hard to estimate the size of their user base. This is especially true for projects which are included in various Linux distributions. Often the only available source of information is the download statistics of one's own web site, but that is less and less useful as the packages become available from distributors as well. Therefore we have an optional usage counting mechanism included in DRBD since release 8.0.
How the usage counting works
When you start DRBD for the first time, its tools will ask you if you would like to participate in this process. If you agree a random number is created on your machine, and this random number is sent with DRBD's version number to usage.drbd.org and is stored on your machine. Should you update your DRBD installation later, the same random number is sent with the new version number.
When you create DRBD's meta data on a block device, you are also eligible to take part in this process. As there are random numbers for the machine there are also random numbers for the devices.
The whole process is completely anonymous, none of your systems' other data (IP etc) is stored in the database.
What is in it for you
On the next pages we provide the results of a few selected queries online. What these results now mean for our user base is still an open question, but this data can serve as a base for anyone who wants to estimate their size.