NonStop S-Series Planning and Configuration Guide (G06.29+)

System Components
HP NonStop S-Series Planning and Configuration Guide—523303-021
4-56
I/O Multifunction (IOMF) CRUs
The 1980 IOMF 2 CRU contains:
•
An amber status LED, that when lit, indicates that the IOMF 2 CRU is in an error
condition.
•
A green power LED, that when lit, indicates that the IOMF CRU is operational.
•
Two service LEDs that are currently unused.
Multifunction I/O Board (MFIOB)
The MFIOBs in IOMF CRUs are identical to those in PMF CRUs. The MFIOB provides:
•
Service processor (SP) functions for the enclosure (group), such as initial power on
for the CRUs within the group and environmental and maintenance functions. The
SPs in IOMF CRUs are always expansion service processors (ESPs).
•
Two SCSI ServerNet addressable controllers (SACs) that connect only to SCSI
devices within the I/O enclosure.
•
One SCSI SAC for an external differential SCSI port.
•
One Ethernet SAC that is used only during system resizing.
•
Interconnection of ServerNet links in the ServerNet fabrics.
For descriptions of these boards, see Multifunction I/O Board (MFIOB) on page 4-45.
Each IOMF CRU connects to one of the ServerNet fabrics through the MFIOB.
The fabric connections are:
The I/O enclosure allows any processor in the associated processor enclosure to
access to both the X and Y fabrics. The internal disk drives in an I/O enclosure can
also access both fabrics.
Power Interlock
The power interlock prevents removal of the IOMF CRU from an enclosure when
external power is applied to the enclosure.
Slot Number of
IOMF CRU
Fabric Connection
Through MFIOB
50 X
55 Y