Select bus-level or IOP-level partitioning

Bus-level partitioning

With bus-level I/O partitioning, you dedicate an I/O bus and all resources on the bus to the same partition. A partition using the bus-level configuration, all I/O (included the alternate IPL device, console, and electronic customer support device) is dedicated and no resources are dynamically switched into or out of the partition. On a server that has partitions at the bus level, all buses are owned dedicated by their respected partitions and no devices are switched.

Bus-level logical partitions allow for:

• Better problem isolation and therefore higher availability.
• Better performance.
• Simplified hardware management.

IOP-level partitioning

When you partition a bus at the IOP level, you share the bus and divide up the I/O resources by IOP. This type of logical partitions allows for:

• Greater flexibility with partition I/O subsystems.
• Potential cost reduction by eliminating some expansion units that you may need to support additional buses.
• Optimization of hardware resources to avoid server limits such as 19 buses per server (only on AS/400e™ models).
• The ability to dynamically switch an IOP from one logical partition to another without the need to restart the server.
• Simplified configuration planning since hardware movement is not necessary.

Additionally, it is possible to configure a partition to utilize both dedicated buses and dedicated IOPs on shared buses.