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

System Components
HP NonStop S-Series Planning and Configuration Guide—523303-021
4-46
Configurations of Memory Units
Service Processor (SP)
The service processor (SP) on the MFIOB monitors and controls the operation of the
system. The SPs:
•
Initialize hardware
•
Configure ServerNet routers
•
Perform startup services
•
Perform down system services
•
Perform environmental sense and control (ESC) functions
•
Control power
•
Test hardware
•
Configure hardware
Each SP has its own operating system that runs independently of other SPs and of the
rest of the system. Thus, SPs allow you to perform operations on a NonStop S-series
server independent of the HP NonStop operating system. Even when the system is
down, the SPs provide a low-level link to the system.
Service processors operate in pairs. Within an enclosure, one SP is the active SP and
the other is the backup SP.
The two SPs in an enclosure are referred to as peer SPs. If one SP in the pair fails, its
peer SP can perform any required function.
Master Service Processors
The SPs in group 01 are called master service processors (MSPs); the SPs in other
enclosures can be called expansion service processors (ESPs). The role of ESPs is
typically limited to functions within a single service processor domain.
The MSPs:
•
Connect to the system console through the Ethernet port on the PMF CRU
•
Provides the external maintenance interface services for the system
•
Provide operating system load control
•
Perform down system services
Service Processor Domains
All modules and CRUs connected to a single serial maintenance bus (SMB) are
controlled by one SP pair and are referred to as a service processor (SP) domain.