14.3.1 Object Message Overview

Messages can be associated with the scheduler, jobs, and nodes. Their primary use is a line of communication between resource managers, the scheduler, and end-users. When a node goes offline, or when a job fails to run, both the resource manager and the scheduler will post messages to the object's message buffer, giving the administrators and end-users a reason for the failure. They can also be used as a way for different administrators and users to send messages associated with the various objects. For example, an administrator can set the message, "Node going down for maintenance Apr/6/08 12pm," on node node01, which would then be visible to other administrators.

14.3.2 Viewing Messages

To view messages associated with a job (either from users, the resource manager, or Moab), run the checkjob command.

To view messages associated with a node (either from users, the resource manager, or Moab), run the checknode command.

To view system messages, use the mschedctl -l message command.

To view the messages associated with a credential, run the mcredctl -c command.

14.3.3 Creating Messages

To create a message use the mschedctl -c message <STRING> [-o <OBJECTTYPE>:<OBJECTID>] [-w <ATTRIBUTE>=<VALUE>[-w ...]] command.

The OBJECTTYPE can be one of the following:

• node
• job
• rsv
• user
• acct
• qos
• class
• group

The ATTRIBUTE can be one of the following:

• owner
• priority
• expiretime
• type

Valid types include:

• annotation
• other
• hold
• pendactionerror

Deleting Messages

Deleting, or removing, messages is straightforward. The commands used depend on the type of object to which the message is attached:

• Scheduler: Use the "mschedctl -d message:<INDEX>" command (where INDEX is the index of the message you want to delete).
  
  
• Node: Use the mnodectl<NODE> -d message:<INDEX> command.