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2.4.2 Consideration of Logical Domain Reconfiguration

2.4.2 Consideration of Logical Domain Reconfiguration
You need to note the following points when reconfiguring hardware resources assigned to a logical domain.
Preparation on the device side
Before reconfiguring a virtual disk and virtual network among virtual I/O devices, perform the following work:
  1. Unmounting the virtual disk
  2. Executing unplumb for the virtual network interface
Delayed reconfiguration for the control and root domains
To statically add a physical I/O to or delete it from the control and root domains, operate it through delayed reconfiguration. Once you reconfigure physical I/Os assigned to the target control and root domains through delayed reconfiguration, any other reconfiguration requests for the control and root domains are postponed until the control and root domains are restarted.
Limit on delayed reconfiguration
You cannot reconfigure the hardware resources for a guest domain when delayed reconfiguration mode is set for the control or root domain to reconfigure hardware resources. Perform reconfiguration work for the guest domain after finishing the reconfiguration work on the control or root domain.
Cancellation of delayed reconfiguration
Use the ldm cancel-operation reconf command to cancel a delayed reconfiguration operation on the control or root domain. For details of the ldm command, see the Oracle VM Server for SPARC Reference Manual.
Logical domain requirements
  1. When dynamically reconfiguring a physical partition, ensure that Oracle Solaris on the control domain has already started.
  2. The disk that configures the system volume on the control domain must be in a redundant configuration. The redundant configuration is required with the disk on both the system board deleted through dynamic reconfiguration and the system board not deleted through dynamic reconfiguration. If the disk is not in a redundant configuration, the control domain cannot be started when the I/O devices have been released in advance to delete the system board where the disk is mounted.
Memory size assigned to the hypervisor
The amount of memory that can be used with the logical domain is less than the amount of memory actually installed in the chassis. This is because the memory used for hypervisor operation is reserved on each chassis. At system configuration, design the domain configuration by subtracting the memory used by this hypervisor. The amount of memory assigned to the hypervisor depends on the model, building block configuration, and PPAR-DR mode setting. For details on PPAR DR mode, see "2.5.3 How to Check/Set PPAR DR Mode."

The hypervisor memory assigned to each physical partition is as follows:
Table 2-9  Amount of Memory Assigned to the Hypervisor
Model PPAR DR Mode
Enabled Disabled
SPARC M12-1/M12-2 2.5 GB
SPARC M12-2S 2.5 GB + (1.5 GB x (number of chassis comprising the physical partition - 1))
SPARC M10-1/M10-4 -
2 GB
SPARC M10-4S 2 GB + (1.25 GB x (number of chassis - 1)) 2 GB + (1.0 GB x (number of chassis - 1))
Placement of CPU cores and memory
To enable disconnection of the system board with physical partition dynamic reconfiguration, be careful when determining the number of CPU cores to be assigned, as well as the memory placement. For details, see "Placement of CPU cores and memory" in "2.5.2 Considerations in System Operation for Dynamic Reconfiguration."