The information provided in this topic defines specific sections of a location code string. Use this information to understand the meaning of a location code.
This topic also provides information about how to read and understand the specific sections of a location code string. A comprehensive list of location codes used by your I/O enclosure is also provided.
Use the following table to link to a specific topic for additional information when reading and understanding your location code.
| Location code topics | Description |
|---|---|
| Location code overview | Contains background information about using location codes. |
| Physical location codes | Provides definitions for physical location codes. |
| Logical location codes | Provides definitions for logical location codes. |
| Location code format | Provides format information of the Un value in the location code string. For example U7031.001. |
| Location code labels | Provides definitions for location code labels. The location code labels begin with an alphabetic character and follow the system serial number. For example, U7031.001.10ABCDE-P3-C31-T2-L23. (The system serial number is the 10ABCDE.) The P3, C31, T2, and L23 all contain an alphabetic character that is identified in the Location code labels table. |
| Worldwide unique identifier | Provides definitions for the worldwide unique identifiers. This group of digits follows the resource code labels and always begins with the letter W. |
Servers (system unit and enclosures) use physical location codes to provide mapping of replaceable units. Location codes are produced by the server's firmware, which structures them so that they can be used to identify specific parts in a system. The location code format is the same for all servers.
If you are working with a specific location code, the unit type and model immediately follow the first character (Utttt.mmm). Match the unit type and model to a link, as shown in the Unit type and locations table.
Physical location codes provide a mapping of logical functions and components (such as backplanes, removable modules, connectors, ports, cables, and devices) to their specific locations within the physical structure of the server.
If the physical location cannot be mapped to a physical location code, the server's firmware generates a logical location code. A logical location code is a sequence of location labels that identifies the path that the system uses to communicate with a given resource.
A resource has as many logical location codes as it has logical connections to the system. For example, an external tape device connected to two I/O adapters will have two logical location codes.
An example of a logical location code is:
Subscribe to this informationU7031.001.10ABCDE-P3-C31-T2-L23The first part of the location code (through the T2 label) represents the physical location code for the resource that communicates with the target resource. The remainder of the logical location code (L23) represents exactly which resource is indicated.
The location code is an alphanumeric string of variable length, consisting of a series of location identifiers, separated by a dash. An example of a physical location for a fan is Un-A1.
The first position, represented by Un (where n is equal to any string contained between the U and the hyphen) in the preceding example, is displayed in one of the forms in the following table.
| Machine type and model number in its location codes | Feature codes and sequence numbers in its location code |
|---|---|
|
|
| The leftmost code is always U. | The leftmost code is always U. |
| tttt represents the unit type of the enclosure (drawer or node). | ffff represents the feature code of the enclosure (drawer or node). |
| mmm represents the model of the enclosure. | ccc represents the sequence number of the enclosure . |
| sssssss represents the serial number for the enclosure. | sssssss represents the serial number of the enclosure. |
| Note: The mmm or ccc number
might not be displayed on all location codes for all servers. If the mmm value
is not displayed, the location code is displayed in one of the following
forms:
|
|
The location code is hierarchical; that is, each location identifier in the string represents a physical part. The order (from left to right), in which each identifier is shown, allows you to determine which parts contain other parts in the string.
The dash (-) separator character represents a relationship between two components in the unit. In the example of the fan, whose location code is Un-A1, the dash shows that the fan (A1) is contained in the base unit (or Un). Modules, adapters, cables, and devices are all parts that are plugged into another part. Their location codes will always show that they are plugged into another part as components of the server. Another example follows:, Un-P1-C9 is a memory DIMM, with memory DIMM (C9) plugged into a backplane (P1), which is inside the unit (Un).
For more information about the various location code label prefixes, refer to Location code labels. To review a list of location codes for your I/O enclosure, refer to 5786, 5787, 7031-D24, and 7031-T24.
The following table describes the location code label prefixes.
| Prefix | Description | Example |
|---|---|---|
| A | Air-moving device | Fan, blower |
| C | Card connector | input/output port (IOP), input/output adapter (IOA), dual inline memory module (DIMM), processor card |
| D | Device | Diskette, control panel |
| E | Electrical | Battery, power supply, ac charger |
| L | Logical path SCSI target | IDE address, fibre channel logical unit number (LUN) |
| N | Horizontal placement for an empty rack location | |
| P | Planar | System backplane |
| T | Port | System unit or enclosure integrated connector |
| U | Unit | Usually consists of the machine type |
| V | Virtual planar | |
| W | Worldwide unique ID | This group of digits follows the resource code labels and always begins with the letter W |
| X | Electronic industries alliance (EIA) spacing value for an empty rack location | Standardized unit of measure used to identify the height of a rack drawer or the usable height space within a rack. |
| Y | Firmware field replaceable unit (FRU) | microprogram or instruction set stored in read only memory (ROM) of your system |
A worldwide unique identifier location label consists of the prefix W followed by a maximum of 16 uppercase hexadecimal digits with no leading zeros. A location code might not consist of a worldwide unique identifier. When present, the worldwide unique identifier location label follows the location label of the resource that interfaces with the resource that has the worldwide unique identifier, usually a port.
