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3.9

# vm-add-lpc-device

- 3.9. vm-add-lpc-device
  - 3.9.1. Name
  - 3.9.2. Description
  - 3.9.3. Example

3.9.1

## Name

1
vm-add-lpc-device - Add an LPC device to a virtual machine
3.9.2

## Description

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The vm-add-lpc-device command adds an LPC device to a virtual machine. The bhyve documentation describes such devices as "LPC PCI-ISA bridges with COM1 and COM2 16550 serial ports and a boot ROM". In practice, LPC devices are used to provide console access to virtual machines, and UEFI firmware to virtual machines that are booting from UEFI.
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### 3.9.2.2 Parameters

Parameter | Type | Required | Description
--- | --- | --- | ---
--add-backend | TTY Backend | true | A specification of the TTY device backend to add
--comment | String | false | A comment describing the new device
--configuration | Path | false | The path to the configuration file (environment variable: $WAXMILL_CONFIGURATION_FILE)
--device-slot | Device Slot | true | The slot to which the device will be attached.
--machine | UUID | true | The ID of the virtual machine
--verbose | Log Level | false | Set the minimum logging verbosity level.
--replace | Boolean | false | true if an existing device in the given slot should be replaced.

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### 3.9.2.3 Device Slot Syntax

    bus        = ? [0 .. 255] ? ;
    slot       = ? [0 .. 31] ? ;
    function   = ? [0 .. 7] ? ;
    deviceSlot = bus , ":" , slot , ":" , function ;

    Examples:
      0:0:0
      255:31:7

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### 3.9.2.4 TTY Backend Syntax

    path         = ? Any unix-like path ? ;
    port         = "com1" | "com2" | "bootrom" ;
    stdioBackend = "stdio" , ";" , port ;
    fileBackend  = "file" , ";" , port , ";" , path ;
    nmdmBackend  = "nmdm" , ";" , port ;
    ttyBackend   = stdioBackend | fileBackend | nmdmBackend ;

    Examples:
      stdio;com1
      file;bootrom;/tmp/xyz
      nmdm;com2

3.9.3

## Example

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### 3.9.3.1 Example

    $ waxmill vm-add-lpc-device \
      --machine de17174a-1b3c-4ebc-80af-cb239aa18cbd \
      --device-slot 0:4:0 \
      --add-backend stdio;com1

    $ waxmill vm-add-lpc-device \
      --machine de17174a-1b3c-4ebc-80af-cb239aa18cbd \
      --device-slot 0:4:0 \
      --add-backend file;bootrom;/usr/local/share/uefi-firmware/BHYVE_UEFI.fd

    $ waxmill vm-add-lpc-device \
      --machine de17174a-1b3c-4ebc-80af-cb239aa18cbd \
      --device-slot 0:4:0 \
      --add-backend nmdm;com1

3.8. vm-add-framebuffer-device
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3. Command-Line Interface
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