3.7.0 HP StorageWorks HP Scalable NAS File Serving Software administration guide - HP Scalable NAS 3.7 for Linux (AG513-96002, October 2009)

When using Samba with HP Scalable NAS, you will need to use a active/passive
configuration, with one node hosting the share and other nodes serving as backups.
The data, or shares, to be exported are stored on PSFS filesystems.
Clients access a share via a virtual Samba server. The virtual server is controlled by
an HP Scalable NAS virtual host, which is configured with one node as the primary
and one or more additional nodes as backups. If the primary node fails, the virtual
host fails over to a backup node. The client connections can then reattach to the
filesystem via the virtual host on the backup node. (Ideally, the ability to seamlessly
move client connections from one node to another without reattaching would be
preferable, but new node and client connections (session states) must be re-established
before operations can continue.)
Because of the connection-based nature of the CIFS protocol and the reconnect logic
in the clients and Samba server, failover will be a disruptive event for the client only
if there is data in-flight at the time of failover.
The backup node for one virtual Samba server can be the primary node for another
virtual server. Also, a node can broadcast multiple PSFS filesystems. The only restriction
is that each PSFS filesystem can be associated with only one virtual Samba server.
The core part of the solution is based on the concept of a Samba “virtual server” and
the methodology is implemented with the use of a Samba macro named “%L”. This
technique allows a Windows client to browse the Network > Workgroup/Domain
and see the configured virtual server in the list of possible servers, including the host
of the virtual server.
Samba configuration400