multihomed host and load balance

[Kevin Darcy]

hoyoung at us.ibm.com wrote:

> All, how would I go about load balancing on a multihomed host?

A rough form of load balancing can be achieved by having a single name which
resolves to multiple IP addresses; modern implementations of named will (by
default) "round robin" the responses so different clients will connect to
different interfaces.For "true" load balancing, however (since not all
connections have an equal impact), you'd need some sort of commercial product
which redirects requests coming into a single IP address to different
interfaces/machines based on performance/capacity metrics measured in
real-time.

> Could each adapter card be associated with a different name?

You could do that, I suppose, if you have good control of your client
configurations and are willing to maintain the separate names forever. Having
a single name seems simpler and more elegant, though, and also offers a
degree of redundancy. Some applications are smart enough to work through a
list of addresses they get in response to a name query, if the first address
in the list is unreachable. In the worst case, the user can keep trying to
connect and they should eventually get through.


- Kevin