DRBD’s authors have written and published a number of papers on DRBD in general, or a specific aspect of DRBD. Here is a short selection:
Lars Ellenberg. DRBD v8.0.x and beyond. 2007. Available at http://www.drbd.org/fileadmin/drbd/publications/drbd8.linux-conf.eu.2007.pdf
Philipp Reisner. DRBD v8 - Replicated Storage with Shared Disk Semantics. 2007. Available at http://www.drbd.org/fileadmin/drbd/publications/drbd8.pdf.
Philipp Reisner. Rapid resynchronization for replicated storage. 2006. Available at http://www.drbd.org/fileadmin/drbd/publications/drbd-activity-logging_v6.pdf