NBD is a protocol for accessing block devices over the network. nbdkit is a toolkit for creating NBD servers. The key features are: * Multithreaded NBD server written in C with good performance. * Minimal dependencies for the basic server. * Liberal license allows nbdkit to be linked to proprietary libraries or included in proprietary code. * Well-documented, simple plugin API with a stable ABI guarantee. Lets you to export "unconventional" block devices easily. * You can write plugins in C or many other languages. * Filters can be stacked in front of plugins to transform the output. In Fedora, 'nbdkit' is a meta-package which pulls in the core server and a useful subset of plugins and filters. If you want just the server, install 'nbdkit-server'. To develop plugins, install the 'nbdkit-devel' package and start by reading the nbdkit and nbdkit-plugin manual pages.