1Remus provides fault tolerance for virtual machines by sending continuous 2checkpoints to a backup, which will activate if the target VM fails. 3 4See the website at https://wiki.xen.org/wiki/Remus for details. 5 6Using Remus with libxl on Xen 4.5 and higher: 7 To enable network buffering, you need libnl 3.2.8 8 or higher along with the development headers and command line utilities. 9 If your distro does not have the appropriate libnl3 version, you can find 10 the latest source tarball of libnl3 at http://www.carisma.slowglass.com/~tgr/libnl/ 11 12Disk replication: 13 VMs protected by Remus need to use DRBD based disk backends. Specifically, you 14 need a compile and install a custom version of DRBD, that is available publicly 15 at https://github.com/rshriram/remus-drbd 16 This code is based on DRBD 8.3.11 and uses a new replication protocol (named 17 protocol D) for asynchronous disk checkpoint replication. A protected VM's DRBD 18 disks on the primary and backup hosts need to be configured to use protocol D 19 as the replication protocol. An example resource configuration file can be found 20 in the aforementioned github repository. 21