Install drbd-doc by entering the following commands in the terminal:
sudo apt update sudo apt install drbd-doc
RAID 1 over TCP/IP for Linux (user documentation)
Drbd is a block device which is designed to build high availability clusters by providing a virtual shared device which keeps disks in nodes synchronised using TCP/IP. This simulates RAID 1 but avoiding the use of uncommon hardware (shared SCSI buses or Fibre Channel). It is currently limited to fail-over HA clusters. . This package contains the DRBD User's Guide in HTML and PDF format.