The Oracle VM Guest Additions daemon, ovmd, facilitates a bi-directional messaging channel between Oracle VM Manager and the guest. It allows first-boot installation configuration, and is capable of sending and receiving messages consisting of key-value pairs.
It is possible to send messages via Oracle VM Manager to the Oracle VM Guest Additions daemon running on any guest, using the ovm_vmmessage utility that can be installed on any Linux system with access to Oracle VM Manager or on the Oracle VM Manager host itself. See Section 2.4.3, “Oracle VM Virtual Machine Messaging (ovm_vmmessage)” for more information on using this tool.
In previous releases you could use the ovmd utility to send key/value messages to a virtual machine. This feature is now included directly in Oracle VM Manager. Although this section mentions the options available to send messages to a virtual machine using ovmd, you should instead use the Oracle VM Manager Web Interface or Oracle VM Manager Command Line Interface to send key/value messages. The virtual machine must have the Oracle VM Guest Additions daemon installed and running. See Send VM Messages in the Oracle VM Manager User's Guide, or the Oracle VM Manager Command Line Interface User's Guide for more information.
Used in conjunction with the ovm-template-config script, the ovmd utility can be used to remotely configure system and application configuration parameters within a virtual machine as it boots. See Section 3.6, “The Oracle VM Template Configuration Script and Modules” for more information on this facility.
Oracle VM Manager makes use of ovmd in order to obtain IP addressing information from the guest to include in the Oracle VM Manager Web Interface when displaying detailed virtual machine information. See Section 3.5, “Displaying the Virtual Machine's IP Address”.
You can run ovmd directly from the command line
to perform actions outside of ovmd's function
as a daemon or system service. Running ovmd
using the --help parameter provides you with a
breakdown of the options supported when run directly from the
command line.
Syntax
ovmd [
{
-p
|
--set-param=
}
param-g
|
--get-param=
}
key-r
|
--delete-param=
}
key-x
|
--delete-params
}
] [
{
-l
|
--list-params
}
] [
{
-e
|
--event=
}
event-s
|
--script=
}
script-d
|
--debug=
}
{
0
|
1
|
2
}
] [
{
-f
|
--pid-file=
}
filename-t
|
--time-period=
}
seconds-v
|
--version
}
] [
{
-h
|
--help
}
]
Options
The following table shows the available options for this command.
Option | Description |
|---|---|
{
|
Set a parameter in the format of
|
{
| Get the value of the parameter by key name. |
{
| Delete the parameter by key name. |
{
| Delete all parameters. |
{
| List all parameters. |
{
| Inject an event. |
{
| Run a script on the virtual machine. |
{
|
Set the debug level. |
{
| Set the path name of the process ID (PID) file. |
{
|
Set the period for daemon mode. The default is
|
{
| Show the ovmd script version number and exit. |
{
| Show help on the ovmd command options. |
Examples
Example 3.3 Sending a message from a virtual machine to Oracle VM Manager
# ovmd -p key1=value1
See Section 3.4.2, “Using the Messaging Channel” for more information on sending and receiving messages using the ovmd script.
Example 3.4 Listing messages sent from Oracle VM Manager on a virtual machine
# ovmd -\-list
{"key1":"value1"}
{"key2":"value2"}