FSPM Architecture

The Oracle FS Path Manager (FSPM) software consists of a path control module (PCM) and a daemon. The PCM integrates with the AIX Multi-Path I/O (MPIO) subsystem. The PCM and daemon run on the host system to present multiple paths as single logical units.

FSPM prevents multiple paths from being presented as multiple disk drives. Every configured multipathed Oracle FS System LUN will be presented as a single disk drive to the operating system. The driver supports failover across redundant paths. The daemon assists with driver configuration and uses the control path to send and receive information about the hosts. It runs as a background process at the user level and looks after management tasks. The daemon sends host attributes to the Oracle FS System system. The software then takes control of the paths, hides actual paths from the operating system, and behaves like a virtual HBA with a single path to each LUN.

Figure 1 illustrates how the FSPM software installed on a SAN host interacts with an Oracle FS System system. Refer to the table below to determine the significance of the lines and colors in the figure.

Table 1 FSPM interaction diagram key
Graphic element	Description
	Data path
	Control path
	Oracle-supplied hardware and software
	Non-Oracle FS System hardware and software
	SAN host kernel space
	SAN host user space

Figure 1 FSPM interaction with an Oracle FS System server FSPM Architecture

Legend

1 User	10 FSPM Path Control Module (PCM)
2 User application	11 iSCSI software initiator (iSCSI)
3 SAN host	12 TCP/IP driver (iSCSI)
4 FSPM daemon	13 HBA driver (FC or iSCSI) or NIC driver (iSCSI)
5 Control paths (all dashed lines)	14 HBA (FC or iSCSI) or NIC (iSCSI)
6 Oracle FS System administrator	15 SCSI over Fibre Channel (FC) or iSCSI over IP (iSCSI)
7 Oracle FS System command line interface (CLI) or graphical user interface (GUI)	16 Data path (all solid lines)
8 Encrypted XML messages over TCP/IP	17 Oracle FS System server
9 Network card	18 Drive Enclosure storage enclosure pool