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Using vme Event Generator

The Virtual Machine event Generator (VME) is a user-mode utility that generates specific events during the appliance boot process and at runtime.

If an appliance is managed, the appliance must use the vme during its boot process to alert the grid controller that the appliance started successfully. If the appliance is unable to start due to an error, such as invalid property settings or not enough available memory, the appliance uses the vme to fail the appliance start and log an error message to the grid controller system log.

The system log is accessed using the grid list log command. You can also use vme during appliance runtime to log critical error messages to the grid dashboard.

By default, when the APK is installed in an appliance, vme always sends the appliance a Started Successfully event. This can be overwritten by appliance-specific scripts that are executed during the appliance boot process.

Usage

vme id=<event> [msg=<message>] [severity=<severity>] [progress=<readiness>] [cnt_name=<counter name> cnt_value=<counter value>]

Examples

vme id=started_ok

vme id=start_failed msg="Missing DNS server address"

vme id=maintenance msg="Database recovery" progress=30

vme id=log msg="SSL certificate loaded OK" severity=info

vme id=alert msg="Corrupted database file detected" severity=fatal

vme id=alert cnt_name=n_db_xact_per_min cnt_value=46 severity=fatal

Notes:

• <event> is one of the following:
  • started_ok - appliance started OK
  • start_failed - appliance failed to start, message is the reason
• maintenance - appliance is in maintenance mode, such as database recovery. Appliances in maintenance mode must report their progress periodically at intervals of 30 seconds minimum.
• log - log an event on behalf of the appliance
• alert - a critical event or error has been detected by the appliance. This is also used to report a change in a counter value
• <counter name> and <counter value> are only used for alerts
• If a message is provided with an alert, the message is logged to the grid dashboard
• <message> is a free text, escaped if spaces or special characters are needed
• <severity> is one of the following:
  • debug - debug information
  • info - informational event
  • warn - warning event
  • error - error event
  • fatal - fatal and irrecoverable error
• <readiness> is reported in percent, valid values are 1 through 100