Attribute Control

Each mpadmin object has a set of attributes that can be modified. Use the set command to specify a value for a given attribute. Use unset to delete an attribute.

Although you can use the set and unset commands to change any cluster attribute, the CRE requires most attributes to have their default values. Be certain to limit your attribute changes to those described in this chapter.

set

Usage:

:: set attribute[=value]

Available In:

Cluster, Node, Partition, Network

The set command sets the specified attribute of the current object.

You must be within the context of the target object to set its attributes. For example, to change an attribute of a specific partition, you must be in that partition's context.

To set a literal or numeric attribute, specify the desired value. The following example sets the node attribute for partition part0. Setting a partition's node attribute identifies the set of nodes that are members of that partition.

[node0]
P(part0):: set node=node1 node2[node0] P(part0):: 

To change the value of an attribute that has already been set, simply set it again. The following example adds node3 to partition part0.

[node0]
P(part0):: set node=+node3[node0] P(part0):: 

As shown by this example, if the value of an attribute is a list, items can be added to or removed from the list using the + and - symbols, without repeating items that are already part of the list.

To set a Boolean attribute, specify the name of the Boolean attribute to be activated. Do not include =value in the expression. The following example enables partition part0.

[node0]
P(part0):: set enabled[node0] P(part0):: 

If you mistakenly set a Boolean attribute to a value--that is, if you follow a Boolean attribute's name with the =value field, mpadmin will ignore the value assignment and will simply consider the attribute to be active.

unset

Usage:

:: unset attribute

Available In:

Cluster, Node, Partition, Network

The unset command deletes the specified attribute from the current object. You must be within the context of an object to unset any of its attributes.

Example:

[node0]
P(part0):: unset enabled[node0] P(part0):: 

disables the partition part0 (that is, makes it unavailable for use).

Remember, you cannot use the set command to set Boolean attributes to the logical 0 ( inactive) state. You must use the unset command.