On our systems at Hetzner we only have a single /64 IPv6 range, which we use to assign addresses to virtual systems, running in Xen and KVM. Because we don’t directly bridge the virtual machines to the external interface, we have written a script that synchronizes Neighbor Discovery entries to the external interface.

HostHenker is a small shell script, which based on whether a daemon is running, adds an entry to /etc/hosts for this host or a fallback host.

Our OCF script for failovers at Hetzner worked flawlessly the last month. Last week, however, a problem arose we did not anticipate.

A second OCF script, which can be used to maintain local DNS entries when using a Hetzner failover setup.

An OCF script that allows you to switch the Failover IP address via the web interface at Hetzner.