NonStop Systems Introduction for H-Series RVUs

Integrity NonStop NS-Series Server Architecture
NonStop Systems Introduction for H-Series RVUs—540083-001
7-3
Software and Hardware Views of Architecture
All input and output to and from each NonStop Blade Element goes through a logical
synchronization unit (LSU). The LSU interfaces with the ServerNet fabrics and
contains logic that compares all output operations of a logical processor, ensuring that
all NonStop Blade Elements agree on the result before the data is passed to the
ServerNet fabrics.
Figure 7-3 on page 7-4 provides a closer view of the ServerNet fabrics. The choice of
the word fabric is significant, contrasting completely with the notion of a bus. Whereas
a bus is conceived as a straightline set of parallel conductors having a start point and
Figure 7-2. Hardware Architecture of Integrity NonStop Servers
VST105.vsd
Logical
Processor
0
Logical
Processor
1
Logical
Processor
2
Logical
Processor
3
LSU
Blade
Element B
Blade
Element A
Blade
Element C
PE
0
PE = processor element
PE
0
PE
0
PE
1
PE
1
PE
1
PE
2
PE
2
PE
2
PE
3
PE
3
PE
3
Triplex
Processor
NonStop Blade Complex
P-switch
P-switch
Dual ServerNet fabrics
P-switch
LSU 0
LSU 1 LSU 2 LSU 3