Commands Reference, Volume 6

wallevent Command

Purpose

Broadcasts an event or a rearm event to all users who are logged in.

Syntax

wallevent [-h]

Description

The ewallevent script always return messages in English. The language in which the messages of the wallevent script are returned depend on the locale settings.

These scripts broadcast a message on an event or a rearm event to all users who are currently logged in to the host when the event or the rearm event occurs. Event or rearm event information is captured and posted by the event response resource manager in environment variables that are generated by the event response resource manager when an event or a rearm event occurs. These scripts can be used as actions that are run by an event response resource. They can also be used as templates to create other user-defined actions.

See the RSCT Guide and Reference to understand how an event response resource runs an action command.

Messages are displayed in this format at the consoles of all users who are logged in when an event or a rearm event for which these scripts are a response action occurs:

Broadcast message from user@host (tty) at hh:mm:ss...

severity event_type occurred for Condition condition_name
on the resource resource_name of resource_class_name at hh:mm:ss mm/dd/yy
The resource was monitored on node_name and resided on {node_names}.

Event information is returned about the ERRM environment variables that are listed and described in the RSCT Guide and Reference, and also includes the following:

Local Time: Time when the event or rearm event is observed. The actual environment variable supplied by ERRM is ERRM_TIME. This value is localized and converted to readable form before being displayed.

The wallevent script captures the environment variable values and uses the wall command to write a message to the currently logged-in user consoles.

Flags

-h: Writes the script's usage statement to standard output.

Parameters

log_file

Specifies the name of the file where event information is logged. An absolute path for the log_file parameter should be specified.

The log_file is treated as a circular log and has a fixed size of 64KB. When log_file is full, new entries are written over the oldest existing entries.

If log_file already exists, event information is appended to it. If log_file does not exist, it is created so that event information can be written to it.

Exit Status

0: Script has run successfully.
1: Error occurred when the script was run.

Restrictions

These scripts must be run on the node where the ERRM is running.
The wall command is used to write a message to currently logged-in user consoles. Refer to the wall man page for more information on the wall command.

Standard Output

When the -h flag is specified, the script's usage statement is written to standard output.

Examples

Suppose the wallevent script is a predefined action in the critical-notification response, which is associated with the /var space used condition on the resource /var. The threshold of the event expression defined for this condition is met, and an event occurs. The critical-notification response takes place, and wallevent is run. The following message is displayed on the consoles of all users who are logged in:
```
Broadcast message from joe@neverland.com (pts/6) at 18:42:03...
 
Critical event occurred for Condition /var space used 
on the resource /var of filesys of IBM.FileSystem at 18:41:50 03/28/02
The resource was monitored on c174n05 and resided on {c174n05}.
```

When a rearm event occurs for the /var space used condition on the resource /var, the following message is displayed on the consoles of all users who are logged in:

Broadcast message from joe@neverland.com (pts/6) at 18:42:03...
 
Critical rearm event occurred for Condition /var space used 
on the resource /var of filesys of IBM.FileSystem at 18:41:50 03/28/02
The resource was monitored on c174n05 and resided on {c174n05}.

Location

/usr/sbin/rsct/bin/ewallevent: Contains the ewallevent script
/usr/sbin/rsct/bin/wallevent: Contains the wallevent script

Related Information

Commands: wall

Books: see the RSCT Guide and Reference for information about the event response resource manager (ERRM) and about how to use ERRM environment variables