HP-UX 11i v3 Dynamic nPartitions - Features and Configuration Recommendations

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Base cells and floating cells
A cell is eligible for online deactivation if and only if it is designated as a floating cell. Any cell not
specifically designated as a floating cell is a base cell. HP-UX before 11i v3 included support for
base cells only. A base cell cannot be online deactivated.
The system administrator designates a cell as a base cell or floating cell using the nPartition
commands. Designation as a floating cell has two important implications. First, a floating cell can
never contain any interleaved memory. 100% of the memory on a floating cell is cell local memory.
Second, the operating system cannot place certain vital data elements in memory on floating cells.
This precaution ensures that the operating system can continue to run at optimal performance if the
floating cell is online deactivated.
The core cell for an nPartition is a base cell; therefore, every nPartition must contain at least one base
cell. The system administrator might designate additional cells as base cells so that the operating
system can have more memory in which to place its vital data elements.
A cell can be online activated as a base cell. In that case, it always contains 100% cell local
memory, but it cannot subsequently be online deactivated.
A cell's designation as base or floating can be changed while the cell is active, however the change
cannot take effect until the partition is rebooted. Similarly, the fraction of cell local memory on a base
cell can be changed while the cell is active, but the change cannot take effect until the partition is
rebooted.
Dynamic nPartitions commands
The static nPartition commands have been augmented with a new command, parolrad, to invoke
cell online operations. This section gives the basics for the command. The full details are available in
the manual pages.
The parolrad command can operate upon remote partitions, but all examples discussed here are
for operations upon the local partition. That is, the partition running the operating system on which
the parolrad is invoked is the target of the cell online operation.
The command for cell online activation is
parolrad –a cell_identifier
where cell_identifier specifies the cell to be online activated. The cell_identifier can
be a global slot number or in the form cabinet number/slot number. It is required that the specified
cell already be assigned to the local partition and be in the inactive state.
The command for cell online deactivation is
parolrad -d cell_identifier
where cell_identifier specifies the cell to be online deactivated. It is required that the
specified cell be an active floating cell in the local partition.
Examples of the use of these commands are given in the appendix Illustrated example of online cell
migration.
As an alternative to the command line interface, Dynamic nPartitions operations can also be initiated
through the Partition Manager graphical user interface tool. In fact, the Partition Manager provides
full support for all of the operations used to manage cell-based HP servers. Documentation for the tool
is available on the Web.
I/O chassis
A cell can have an I/O chassis attached to it. Depending on the model of the server, a cell can also
have core I/O associated with it.