4.0.0 HP Polyserve Matrix Server Administration Guide (T5392-96052, March 2010)

server name will actually be served by the virtual host—basically, a failover-pro-
tected version of the server, with no difference in appearance to the clients.
• Keep the existing name on the server. If you do not rename the server, clients will
need to use the new virtual host name to benefit from failover protection. Clients
can still access the server by its name, but those requests are not protected by
Matrix Server. If the server fails, requests to the server’s hostname fail, whereas
requests to the new virtual hostname are automatically redirected by Matrix
Server to a backup server.
Configure servers for DNS load balancing
Matrix Server can provide failover protection for servers configured to provide domain
name service (DNS) load balancing. DNS load balancing allows you to set up servers
so that requests are sent alternately to each of the servers in a cluster. For example,
clients could access acmd1 and acmd2 in turn, enabling the servers to share the
load of accepting and responding to client requests.
DNS includes a round-robin feature using address records (A records) to alternate
requests between IP addresses. This feature provides a straightforward way to gain
load balancing capability and simplified load balancing, resulting in improved
response time.
Matrix Server provides failover protection for this configuration. Without Matrix
Server, requests are simply alternated between the servers. If a server goes down,
requests to that server do not connect.
To configure for round-robin load balancing with Matrix Server, you define virtual
hosts as addresses in the A records on the DNS. Then use Matrix Server to associate
primary and backup servers with that virtual host. In essence, you use the virtual host
capability of Matrix Server to accept the round-robin requests sent by the DNS. Matrix
Server handles the failover function to the real servers in the cluster.
Following is a simple example to demonstrate this capability. (The example may not
be applicable to your specific usage environment.) In the example, two servers,
acmd1 and acmd2, are configured to accept round-robin requests.
Configure servers62