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Chapter 1: Introduction to the EIU 41
The information in table 2 defines the port requirements for EIU installation.
Table 2
Peripheral |
| Message Switch |
| Comments |
|
|
|
|
|
| links per plane | Port Card | Paddle Board |
|
|
|
|
|
|
LPP | 4 | NT9X17AA | NT9X23BA | 1 LPP requires 1 |
|
|
|
| MS port card |
|
|
|
|
|
EIU provisioning
Provisioning of EIUs is application dependent. The number of EIUs required and their configuration is determined by a combination of product and software criteria. EIUs are not provisioned on a switch unless required by the application.
Where possible, provision two or more EIUs connecting to a single LAN to improve reliability. This redundancy may not be required if duplication is provided at a higher system level (for example, duplicate LANs).
Observe the following provisioning rules:
•although the maximum number of EIUs in a switch is limited to eight (limitation imposed by software), the actual number that you can provision per platform is determined by engineering rules (refer to Provisioning Rules for LPP, SSLPP, and SNSE LIS, System Engineering Bulletin SEB
•each EIU requires one LIU position (two slots) in a
•each EIU has a fixed memory capacity; the NTEX22BB contains 8 Mbyte of RAM, and the NTEX22CA contains 32 Mbyte of RAM
For more information on datafill, refer to “Chapter 3: EIU datafill”. For more information on maintenance impact on spares, refer to “EIU sparing requirements” on page 101.
EIU sparing and redundancy
The DMS switch and the EIU support load balanced routing. Characteristics related to provisioning and options are described in the following points:
•In table IPNETWRK, one EIU is defined as the default for the CM.
•In table IPROUTER, all EIUs are defined.
•Maintenance software ensured that all EIUs are aware of the states of all other EIUs. States are known for the following:
—links between the EIU and the
—links between the EIU and the