Load source placement rules for i5/OS logical partitions

Each i5/OS^® logical partition requires a load source disk unit. The server uses the load source to start the logical partition. Each logical partition has a specific slot placement for its load source depending on the type of system unit or expansion unit where the load source is installed. An IOP or IOA is then required to control the load source disk unit for each logical partition.

Note: The information provided does not replace the LPAR Validation Tool (LVT). Use this information as a resource with the LVT output. Its purpose is to assist you in the load source placement for your i5/OS logical partitions. For more information on the LVT, see LPAR Validation Tool (LVT).

The load source disk for an i5/OS logical partition must be placed as follows.

Server or expansion unit	IOA	Disk slot
520	Imbedded controller	P3-D2, P3-D3, P3-D4
520	SCSI bus port 0 of Optional PCI storage IOA controlling P2 disk slots	P2-D2, P2-D3, P2-D4
550	Imbedded controller	P2-D2, P2-D3, P2-D4
550	SCSI bus port 0 of Optional PCI storage IOA controlling P3 disk slots	P3-D2, P3-D3, P3-D4
570	Imbedded controller	P3-D4, P3-D5, P3-D6
595	SCSI bus port 0 of any storage IOA to which a load source disk unit is connected in the base PCI-X expansion tower (9194)	D01, D02, D11, D12, D21, D22, D06, D07, D16, D17, D26, D27, D31, D32, D33, D34 of base PCI-X expansion tower (9194)
5074 or 5079	IOA controlling DB3	D31, D32, D33, D34
	IOA controlling DB1	D01, D02
	IOA controlling DB2	D06, D07
5094 or 5294	SCSI bus port 0 of any storage IOA to which a load source disk unit is connected.	D01, D02, D11, D12, D21, D22, D06, D07, D16, D17, D26, D27, D31, D32, D33, D34
5095	IOA controlling DB1	D01, D02, D03, D04
5095	IOA controlling DB2	D07, D08, D09, D10
5786 or 5787	SCSI bus port 0 of any storage IOA to which a load source disk unit is connected	P1-D1, P1-D2, P1-D3 can contain the load source only if slot C3 contains a single SCSI (506E) repeater card that is connected to port 0 on a SCSI I/O Adapter (IOA) in the system unit but is not connected to slot C2. P1-D7, P1-D8, P1-D9 can contain the load source only if the SCSI repeater card in slot C2 is connected to port 0 on a SCSI IOA in the system unit. P2-D1, P2-D2, P2-D3 can contain the load source only if slot C4 contains a single SCSI (506E) repeater card that is connected to port 0 on a SCSI IOA in the system unit but is not connected to slot C5. P2-D7, P2-D8, P2-D9 can contain the load source only if the SCSI repeater card in slot C4 is connected to port 0 on a SCSI IOA in the system unit.
5790	SCSI bus port 0 of any storage IOA to which a load source disk unit in a 5786 or 5787 expansion unit is connected	P1-D1, P1-D2, P1-D3 can contain the load source only if slot C3 contains a single SCSI (506E) repeater card that is connected to port 0 on a SCSI I/O Adapter (IOA) in the 5790 expansion unit but is not connected to slot C2. P1-D7, P1-D8, P1-D9 can contain the load source only if the SCSI repeater card in slot C2 is connected to port 0 on a SCSI IOA in the 5790 expansion unit. P2-D1, P2-D2, P2-D3 can contain the load source only if slot C4 contains a single SCSI (506E) repeater card that is connected to port 0 on a SCSI IOA in the 5790 expansion unit but is not connected to slot C5. P2-D7, P2-D8, P2-D9 can contain the load source only if the SCSI repeater card in slot C4 is connected to port 0 on a SCSI IOA in the 5790 expansion unit.

Read the following rules about load source placement for i5/OS logical partitions:

The load-source IOP or IOA must be specified when you create your logical partition.
Disk compression must be disabled for the load source disk.
Disk units must have at least 8 GB of usable capacity for i5/OS V5R3M0 or 17 GB of usable capacity for i5/OS V5R3M5 or later.
Disk mirroring requires two load source disk devices in valid load-source positions.
External disk units cannot be used (except for those located in a SAN).
Any disk IOP or IOAs that can attach to a system capable of having logical partitions can be used for additional storage capacity after the special requirements for the load-source disk are met.
Each logical partition has its own single-level storage and hence its own ASP configuration. The ASP configuration rules that apply to systems without logical partitions also apply to logical partitions.
Disk protection can be defined for a partition in the same way as for a nonpartitioned system: parity protection (RAID), mirroring, or mixed. Bus-level mirroring requires two buses in the partition. IOP-level partitioning requires two disk IOPs in the partition.
Disk units that are already in use by a logical partition cannot be easily added to a different logical partition. You must first remove them from the configuration of the partition that is using the disk units before you add them to a different partition. In doing this, the system automatically moves any user or system data to other disk units in the same ASP.
For a 5094 or 5294, you can attach load source disk units to a maximum of six storage IOAs. Also, a 5094 or 5294 can have load source disk units for up to six i5/OS logical partitions.