Introducing HP-UX 11i Virtual Partitions

Sep 2007 9
HP-UX 11i Virtual Partitions operational overview
To understand how vPars works at a high level, it is best to compare it to a generic HP-UX server.
Figure 4 shows a 4-way HP-UX server. Without vPars, the entire server would run a single instance
of HP-UX. All of the resources (CPU, memory and disk) would be dedicated to the applications
running in this single instance. The software stack for this server would look like the one in Figure 5.
Processor
0
Host PCI Bridge
4
Host PCI Bridge
5
SCSI
0/0
Main
Memory
(4GB)
6
Processor
1
Processor
2
Processor
3
Disk
6.0
SCSI
0/0
Disk
6.0
Console
2/0
LAN
1/0
LAN
1/0
Figure 4: Generic HP-UX server block diagram
Application 1
HP-UX 11i
Hardware/Firmware
Application 2
Figure 5: Generic HP-UX server software stack
Using vPars, the server in Figure 4 can be broken into two partitions, each with a subset of the
hardware (Figure 6). Each vPar has its own boot disk, at least one CPU and one LAN connection,
and enough memory to run HP-UX and the applications that will be hosted on this vPar. Since each
vPar can run its own copy of HP-UX (even at different patch levels), each is completely isolated
from software errors, system panics, etc. A software stack for two vPars is shown in Figure 7.