HP StorageWorks Using Hummingbird Maestro Server with the HP Windows Clustered Gateway Application Notes (432208-001, October 2006)

NFS Maestro can be used to export a Clustered File System (CFS). NFS Maestro is installed on each node

that provides NFS services and is then configured to export the appropriate file systems. NFS Maestro then

creates the shares used for the export.

Note that an individual file system should be exported by only one node at a time. The supported cluster

configuration is one active node exporting the file system and one or more nodes acting as backups.

CFS uses virtual hosts to provide failover support for NFS clients accessing the exported file systems. NFS

clients use the IP address of the virtual host to access the server actively exporting the file system. If that

node goes down or the NFS service fails on that node, the virtual host is failed over to a backup node. NFS

client requests then go to the backup node, which is now exporting the file system.

A custom monitor is associated with each virtual host. This monitor watches the NFS service on the primary

and backup nodes and causes the virtual host to fail over if necessary. The NFS services deployment kit

includes a custom script that needs to be installed on each server. When you configure the custom monitor,

you specify that this script is to be used.

In the following example, three virtual hosts are providing access to different file systems. Each virtual host

is primary on a different node. A virtual host could also be created on node 4 to export another file system.

NFS clients are configured to access specific file systems via the virtual hosts.

For example, clients for the \data1 file system access Vhost1 and clients for

the \data3 file system access Vhost3.

Node 1

primary

Vhost1

backup

Vhost2

Node 4

backup

Vhost3

Node 3

primary

Vhost3

Node 2

primary

Vhost2

backup

Vhost1

Ethernet

Shared PSFS File Systems Exported via NFS

Each virtual host provides access to a different set of file systems and is

active on only one server. If the NFS service goes down on a primary node,

the virtual host fails over to a backup node, which then exports the file system

to the clients.