On Linux for s/390: Load Balancer issues
a gratuitous ARP to move IP addresses from one Load Balancer to another.
This mechanism is therefore tied to the underlying network type. When
running Linux for s/390, Load Balancer can natively do high availability
takeovers, complete with IP address moves, only on those interfaces
which can issue a gratuitous ARP and configure the address on the
local interface. This mechanism will not work properly on point-to-point
interfaces such as IUCV and CTC and will not work properly in certain
configurations of qeth/QDIO.