HP-UX HB v13.00 Ch-17 - vPars

HP-UX Handbook – Rev 13.00 Page 6 (of 46)

Chapter 17 Virtual Partitions (vPars)

October 29, 2013

vPar Monitor

Application Application

Hardware / Firmware

HP-UX 11i OE

vPar 2

vPar 1

The vPars monitor manages the assignment of the hardware resources to the virtual partitions,

boots virtual partitions and their kernels, and emulates certain firmware calls. Once a virtual

partition is launched, the monitor transfers the ownership of the hardware to the virtual partition.

The commands for the vPars monitor are shown in section Monitor Commands or at

http://docs.hp.com.

To run a vPar the monitor needs a database where all partitions configuration information is

stored. The vPars database is called /stand/vpdb and resides on each virtual partition (by

default on the boot device).

The vPars database is created with the first vPar. The default is /stand/vpdb, but alternate

database configurations are possible. It stores the partition name, resources such as CPU,

memory, LBAs, boot devices, boot options. You can create, modify, and view the database

contents using vPars commands.

Once the monitor is booted, the selected database is copied into memory and becomes the

“master copy”. The master copy is used to compare and synchronize the other run state vPars. If

the database does not exist on the vPar during boot-up, it will be created. The operating system

of each virtual partition also keeps a local copy of the partition database in a file, by default

/stand/vpdb, on its local boot disk.

Whenever you execute a vPars command from the shell of a partition, the change is first made to

the monitor’s master copy. Then, the local copy is updated from the master copy. The operating

system of each running partition automatically updates its local copy from the master copy every

five seconds. This synchronization ensures that the virtual partitions and changes to the partition

database are preserved, when the entire hard partition is rebooted.

NOTE: The monitor can only synchronize to the database files of running virtual partitions. If

you reboot the hard partition, you should boot the monitor from the boot disk of a virtual

partition that was running during your most recent partition configuration change.