This chapter helps you prepare for a multiple-partitioned environment, including information about requirements, host name considerations, and managed system operating states.
This section contains information about the requirements you must have in order to create partitions.
You should do the following before creating partitions:
Before you start using partitioning, you must determine the following:
For logical partitions, you must assign resources by creating partition profiles. Use the following guidelines for assigning resources in logical partition profiles.
Each processor installed and configured on your system can be individually assigned to a logical partition. You must assign at least one processor to each logical partition.
The HMC can assign memory to a logical partition in increments of 256 MB, with a minimum of 256 MB per partition. One GB is equal to 1024 MB. This section describes the HMC's various logical partition memory considerations.
The system requires some memory overhead when it creates logical
partitions. Use the following table to help you determine how much
memory overhead the system needs for partitioning. You can also use
this table to determine the maximum number of partitions you can
create.
Total Memory (in GB) | Approx. Memory Overhead (in GB) | Approx. Usable Partition Memory (in GB) | Maximum Number of Partitions:
AIX or Linux, any version Pre-10/2002 firmware <=16GB and >16GB (see Notes 1 and 2) | Maximum Number of Partitions:
AIX 5.1 Post-10/2002 Firmware <=16GB and >16GB (see Notes 1 and 3) | Maximum Number of Partitions:
AIX 5.2 (+) or Linux Post-10/2002 firmware All partition sizes (see Notes 1, 4, and 5) |
---|---|---|---|---|---|
4 | .75 to 1 | 3 to 3.25 | 3 and 0 | 13 and 0 | 13 |
8 | .75 to 1 | 7 to 7.25 | 6 and 0 | 16 and 0 | 16 |
16 | .75 to 1 | 15 to 15.25 | 14 and 0 | 16 and 0 | 16 |
24 | 1 to 1.25 | 22.75 to 23 | 16 and 0 | 16 and 0 | 16 |
32 | 1 to 1.25 | 30.75 to 31 | 16 and 0 | 16 and 0 | 16 |
48 | 1.25 to 1.75 | 46.25 to 46.75 | 16 and 1 | 16 and 1 | 16 |
64 | 1.5 to 2 | 62 to 62.5 | 16 and 2 | 16 and 2 | 16 |
96 | 2 to 2.5 | 93.5 to 94 | 16 and 4 | 16 and 4 | 16 |
128 | 2.5 to 3.5 | 124.5 to 125.5 | 16 and 6 | 16 and 6 | 16 |
192 | 3.5 to 4.5 | 187.5 to 188.5 | 16 and 10 | 16 and 10 | 14 |
256 | 5 to 6 | 250 to 251 | 16 and 14 | 16 and 14 | 16 |
Notes:
There are some special memory options to consider when assigning memory to a partition.
When you create a partition profile and select the memory sizes, you can select a box called Small Real Mode Address Region. This option allows you to:
To use the Small Real Mode Address Region option, you must have either Linux or AIX 5.2 installed in the partition. If you check the Small Real Mode box and have the required operating system on your partition, you do not have to follow the following memory boundary rules.
AIX 5.1 may not boot in a partition with the Small Real Mode Address Region option selected, because AIX 5.1 requires a Real Mode Address Region that scales with the size of the overall partition. If you meet these operating system requirements and check the Small Real Mode Address Region box, then the following memory allocation restrictions do not apply.
If you do not select the Small Real Mode Address Region option, then when
you assign your minimum, desired, and maximum memory amounts in the partition
profile, all three memory values will be constrained to be within a specific
range. Each range is associated with a scalable Real Mode Address
Region of a particular size (256 MB, 1 GB, and 16 GB). The Real Mode
Address Region size is automatically determined by the maximum partition
memory size that you specify. These memory ranges are defined in the
following table:
Maximum Memory Size (in GB) | Real Mode Address Region size (in GB) | Partition Memory Range (in GB) |
---|---|---|
Up to 4 | .25 | .25 to 4 |
4.25 to 16 | 1 | 1 to 16 |
16.25 to 256 | 16 | 16 to 256 |
Because large Real Mode Address Regions have more constraints when placed in memory, use the following guidelines when you are planning to create partitions that do not use the Small Real Mode Address Region option:
I/O is assignable to a given partition on a PCI adapter-slot basis.
Because each partition requires its own separate boot device, the system must have at least one boot device and associated adapter per running partition.
Each partition should have at least one network adapter, although this is not mandatory. In addition to providing a network connection, the connection is also needed to provide the capability for HMC service functions. For more information , see Customizing Network Settings.
For more information about a specific device and its capabilities, see the documentation shipped with that device. For a list of supported adapters and a detailed discussion about adapter placement, refer to the PCI Adapter Placement Reference, order number SA38-0538.
You must assign I/O resources to your affinity partitions by creating partition profiles.
The HMC pre-allocates processors and memory to affinity partitions. You can choose to create either 4-processor affinity partitions or 8-processor affinity partitions. If you have 32 processors on your system, choosing a 4-processor group allows you to create up to eight affinity partitions. Likewise, an 8-processor group allows you to create up to four affinity partitions. You cannot define 4-processor groups and 8-processor groups at the same time.
The user allocates I/O to each affinity partition. I/O is assignable to a given partition on a PCI adapter-slot basis. You can also dynamically reassign I/O between affinity partitions.
Because each partition requires its own separate boot device, the system must have at least one boot device and associated adapter per partition.
Each partition should have one network adapter, although this is not mandatory. In addition to providing a network connection, the connection is also needed to provide the capability for HMC service functions. For more information , see Customizing Network Settings.
For more information about a specific device and its capabilities, see the documentation provided with that device. For a list of supported adapters and a detailed discussion about adapter placement, refer to the PCI Adapter Placement Reference, order number SA23-2504.
Each partition, including the Full System Partition, must have a unique host name that can be resolved. Host names cannot be reused between the Full System Partition and the logical partitions. If you need to change the the host name of the partition manually, you may need to update the Network Settings on the HMC. You will need to update if a "short" partition name is used or if a DNS server is not used. For more information about changing the host name manually, seeChanging a Partition Host Name Manually. See Customizing Network Settings to determine if any additional changes are needed.
The HMC Contents area displays an operating state for the managed system.
The following operating states apply to the managed system:
State | Description |
---|---|
Initializing | The managed system is powered on and is initializing. |
Ready | The managed system is powered on and operating normally. |
No Power | The managed system is powered off. |
Error | The managed system's operating system or hardware is experiencing
errors.
For recovery information, see Managed System Operating States. |
Incomplete | The HMC cannot gather complete partition, profile, or resource
information from the managed system.
For recovery information, see Managed System Operating States. |
No Connection | The HMC cannot contact the managed system.
For recovery information, see Managed System Operating States. |
Recovery | The partition and profile data stored in the managed system must be
refreshed.
For recovery information, see Managed System Operating States. |
Version Mismatch | Your managed system's service processor level is higher than your
HMC's code level.
For recovery information, see Managed System Operating States. |
CUOD CTA | You must accept the CUoD license.
For recovery information, see Managed System Operating States. |
The following operating states apply to the logical partition you have
created.
State | Description |
---|---|
Ready | The partition is not active but is ready to be activated. |
Starting | The partition is activated and is undergoing booting routines. |
Running | The partition has finished its booting routines. The operating system might be performing its booting routines or is in its normal running state. |
Error | This partition failed to activate due to a hardware or operating system
error.
For recovery information, see Appendix C, Error Messages and Recovery Information. |
Not Available | This partition is not available for use. Reasons can
include:
For recovery information, see Appendix C, Error Messages and Recovery Information. |
Open Firmware | The partition was activated by a profile that specified an OPEN_FIRMWARE boot mode. |