HP StorageWorks Clustered File System 3.6.0 Windows Storage Server Edition Administration Guide (403103-005, January 2008)

Table Of Contents
Chapter 5: Configure Servers 52
Migrate Existing Servers to HP Clustered
File System
In HP Clustered File System, the names of your servers should be
different from the names of the virtual hosts they support. A virtual host
can then respond regardless of the state of any one of the servers.
In some cases, the name of an existing server may have been published as
a network host before HP Clustered File System was configured. You can
either reassign the public name of the server to the virtual host, which is
generally the better solution, or keep the published name associated with
the server.
Migrate the existing server name to a virtual hostname. In this case,
you will need to assign a new name to the server. External sites that
then access the original server name will actually be served by the
virtual host—basically, a failover-protected 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 HP Clustered File System. If
the server fails, requests to the servers hostname fail, whereas
requests to the new virtual hostname are automatically redirected by
HP Clustered File System to a backup server.
Configure Servers for DNS Load Balancing
HP Clustered File System 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.