Home > Articles > Networking > Storage

  • Print
  • + Share This
Like this article? We recommend

Platform and Domain Configuration

This section describes how to configure platform and domain resources.


The CPU/Memory and MaxCPU boards have one flash programmable read only (FPROM) for each SBBC (boot bus controller) that is associated with a pair of CPUs. Hence, there are two on each CPU/Memory board and one on each MaxCPU. Each of these board types within the entire platform should be maintained at the same flash versions. CPU/Memory boards are interchangeable between the Sun Fire 15K server and the Sun Fire 3800/4800/6800 server lines. It is highly recommended that upon replacement of the CPU/Memory board, the FPROM be updated with the current SMS software version. Any boards removed from a Sun Fire 15K server and inserted into a Sun Fire 3800/4800/6800 server should be similarly updated.


Maintain the same flash versions on all boards in the platform. In particular, verify that the firmware of a newly installed board matches the firmware of all other boards in the platform.

Domain Resources Redundancy

To provide for full redundancy of resources and maximize availability, the minimum domain configuration should consist of two expanders where each is populated with CPU/Memory and hsPCI boards and configured with the identical resources. Several multipathing solutions are available. Whenever possible, use IPMP for network multipathing and Sun StorEdgeTM Traffic Manager software (formerly known as MPxIO) for disk storage multipathing.


Use redundant resources within a domain.

Split Expander Configuration

A split expander is defined as one where the slot 0 board resources reside in a different dynamic system domain than the slot 1 board resource on that expander. While the use of split expanders is fully supported, you should be aware of the fact that this can lead to a slight degradation in performance of some applications. This is due to the fact that there is a two-clock delay on each address request and a two-clock delay on each data response transaction within a split expander. In addition, a split expander becomes a single point of failure for the two domains in which it is configured.


Avoid a split expander configuration if possible.

Slot-Associated DC Circuit Breakers

It is standard operating procedure and considered best practice to engage and leave in the ON position all of the slot-associated DC circuit breakers. SMS hardware access daemon (HWAD) is constantly polling for device presence in the expander slots. If an expander is present and the circuit breaker is in the OFF position, HWAD messages are continually logged, indicating that the device is not responding. Do not use the circuit breakers to power off expander boards for insertion, removal, or any other non-emergency reason unless directed by Sun Service personnel. Use the poweroff SMS command to power off the expander boards.


Leave all DC circuit breakers in the ON position.

Boot Device Attachment Point ID

A Sun Fire 15K server can accommodate 1 to 18 domains. Each domain requires a minimum of one CPU/Memory board with memory installed, an I/O board, a boot device, and a network interface. Within a given domain, the lowest numbered successfully posted domain I/O board contains the Golden IOSRAM and the network connection for the MAN network. As previously stated, it is highly recommended that you configure domains to include multiple I/O boards. Not only does this give you multiple paths to boot device and network resources, it provides redundancy of the IOSRAM and internal domain console networks.

Product Technical Support (PTS) recommends that the boot path for a domain reside on the lowest numbered I/O board, as it is already assigned as a primary domain, resource that normally is not detached from regular system use. I/O devices that will be removed via hot swapping should be installed in other I/O boards.

The highest numbered CPU/Memory board in the domain is assigned to perform boot services. If installed with sufficient memory resources, it usually contains the Solaris OS kernel cage resident in its physical address space at boot time. The primary purpose of the kernel cage is to facilitate the ability to perform DR without having to interrupt the execution of threads. Further discussion on the kernel cage and DR is included in "Dynamic Reconfiguration" on page 22.


Install boot device and domain network interfaces in the lowest numbered I/O board in the domain. Hot-swapped I/O devices should be installed in the non-lowest numbered IO board. Configure the domain with multiple I/O boards for redundancy.

  • + Share This
  • 🔖 Save To Your Account