Abstract
This tip complements the HSL Redpaper (REDP3652) by offering details on the HSL configuration rules, which are unique to the iSeries Model 825.
Contents
The Model 825 has a unique set of rules that influence the maximum number of components on a high-speed link loop. As such, rules specific to the Model 825 warrant a more detailed description than what is presented in the IBM Redpaper High-speed Link Loop Architecture for the IBM eServer iSeries Server, REDP-3652. TIPS0297 complements the HSL Redpaper.
The HSL configuration rules, unique to the Model 825, include the following considerations. The most restrictive rule takes precedence:
- The C loop can accommodate a maximum of six PCI-X or PCI towers, eight Integrated xSeries Adapters (IXAs), or a combination of numbers, not to exceed a total of nine. Represented as an equation, this rule is stated as: 6 + 8 = 9.
- Loops A and B can accommodate a maximum of six PCI-X towers, five PCI towers, five IXAs, or a combination of numbers, not to exceed a total of nine. Represented as an equation, this rule is stated as: 6 + 5 = 9.
- The total of the three loops can provide a system maximum of 27 I/O towers and IXAs.
- Because the A and B loops share a common hub, the Model 825 can only have five PCI towers and IXAs. This can limit the system maximum to less than the stated maximum of 27 I/O towers and IXAs per system.
- If you have the maximum of five PCI towers on loops A or B, you can also have one PCI-X tower on the loop for a total of six, but nothing else can be added. Represented as an equation, this rule is stated as: 5 + 1 = 6. This configuration option lessens the system maximum to as few as 21, depending on whether both loops A and B are populated this way.
- If you have some combination of PCI towers and IXAs equaling five on the A or B loops, you can fill out the loop with a PCI-X tower for a total of six. This configuration option lessens the system maximum to as few as 21.
- If you have the maximum of five IXAs on loops A or B (that is, there are no PCI towers), you can also have up to four PCI-X towers on the loop, and no PCI towers can be added. Represented as an equation, this rule is stated as: 5 + 4 = 9. This configuration option still allows a possible system maximum of 27.
The following table shows the loop maximums on a base Model 825 3/6-way system for PCI and PCI-X towers, and Integrated xSeries Adapters.
Base Model 825 3/6-way Loop designation | No IXA Total towers per loop | Total IXA | Total IXA and Migrated Towers | Single Loop Total Towers Including IXA |
| 1st loop (A) | 6 | 5 | 5 | 9 |
| 2nd loop (B) | 6 | 5 | 5 | 9 |
| 3rd loop (C) | 6 | 8 | 9 | 9 |
Special Notices
This material has not been submitted to any formal IBM test and is published AS IS. It has not been the subject of rigorous review. IBM assumes no responsibility for its accuracy or completeness. The use of this information or the implementation of any of these techniques is a client responsibility and depends upon the client's ability to evaluate and integrate them into the client's operational environment.