Using and Administering

Administration File Structure and Syntax

The administration file is called LoadL_admin

and it lists and defines the machine, user, class, group, and adapter stanzas.

Machine stanza

Defines the roles that the machines in the LoadLeveler cluster play. See Step 1: Specify Machine Stanzas for more information.

User stanza

Defines LoadLeveler users and their characteristics. See Step 2: Specify User Stanzas for more information.

Class stanza

Defines the characteristics of the job classes. See Step 3: Specify Class Stanzas for more information.

Group stanza

Defines the characteristics of a collection of users that form a LoadLeveler group. See Step 4: Specify Group Stanzas for more information.

Adapter stanza

Defines the network adapters available on the machines in the LoadLeveler cluster. See Step 5: Specify Adapter Stanzas for more information.

Stanzas have the following general format:

Figure 23. Format of Administration File Stanzas

label: type = type_of_stanza keyword1 = value1 keyword2 = value2 ...

The following is a simple example of an administration file illustrating several stanzas:

Figure 24. Sample Administration File Stanzas

machine_a: type = machine central_manager = true # defines this machine as the central manager adapter_stanzas = adapter_a # identifies an adapter stanza class_a: type = class priority = 50 # priority of this class user_a: type = user priority = 50 # priority of this user group_a: type = group priority = 50 # priority of this group adapter_a: type = adapter adapter_name = en0 #defines an adapter

The characteristics of a stanza are:

• Every stanza has a label associated with it. The label specifies the name you give to the stanza.
• Every stanza has a type field that specifies it as a user, class, machine, group, or adapter stanza.

• New line characters are ignored. This means that separate parts of a stanza may be included on the same line. However, it is not recommended to have parts of a stanza cross line boundaries.
• White space is ignored, other than to delimit keyword identifiers. This eliminates confusion between tabs and spaces at the beginning of lines.
• A cross-hatch sign (#) identifies a comment and may appear anywhere on the line. All characters following this sign on that line are ignored.
• Multiple stanzas of the same label are allowed, but only the first label is used.
• Default stanzas specify the default values for any keywords which are not otherwise specified. Each stanza type can have an associated default stanza. A default stanza must appear in the administration file ahead of any specific stanza entries of the same type. For example, a default class stanza must appear ahead of any specific class stanzas you enter.