Managing MC/ServiceGuard NFS A.11.11.03 and A.11.23.02 (June 2004)

Overview of MC/ServiceGuard NFS
Chapter 18
MC/ServiceGuard NFS is a tool kit that enables you to use
MC/ServiceGuard to set up highly available NFS servers.
You must set up an MC/ServiceGuard cluster before you can set up
Highly Available NFS. For instructions on setting up an
MC/ServiceGuard cluster, see the Managing MC/ServiceGuard manual.
MC/ServiceGuard NFS is a separately purchased set of configuration
files and control scripts, which you customize for your specific needs.
These files, once installed, are located in /opt/cmcluster/nfs.
MC/ServiceGuard allows you to create high availability clusters of HP
9000 Series 800 computers. A high availability computer system allows
applications to continue in spite of a hardware or software failure.
MC/ServiceGuard systems protect users from software failures as well as
from failure of a system processing unit (SPU) or local area network
(LAN) component. In the event that one component fails, the redundant
component takes over, and MC/ServiceGuard coordinates the transfer
between components.
An NFS server is a host that “exports” its local directories (makes them
available for client hosts to mount using NFS). On the NFS client, these
mounted directories look to users like part of the client’s local file system.
With MC/ServiceGuard NFS, the NFS server package containing the
exported file systems can move to a different node in the cluster in the
event of failure. After MC/ServiceGuard starts the NFS package on the
adoptive node, the NFS file systems are re-exported from the adoptive
node with minimum disruption of service to users. The client side hangs
until the NFS server package comes up on the adoptive node. When the
service returns, the user can continue access to the file. You do not need
to restart the client.
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