---
name: "ldomctl"
section: "8"
platform: "openbsd"
package: "man"
version: "8.0-current-20261101"
release: "OpenBSD 8.0-current (2026-11-01)"
platforms: ["openbsd"]
url: "https://new.carta.tech/ldomctl"
---

# ldomctl(8)

Logical Domain management interface

## NAME

**ldomctl** – Logical Domain management interface

## SYNOPSIS

**ldomctl** *command* \[*argument* *...*\]

## DESCRIPTION

The **ldomctl** program is used to manage logical domains on sun4v systems. It can be used to assign resources to the primary and guest domains, start and stop guest domains from the primary domain, and to display information about domains running on the system.

The following commands are available:

- **create-vdisk** **-s** *size* *file*

  Create a virtual disk image with the specified *file* path and *size*, in bytes. *size* can be specified with a human-readable scale, using the format described in scan\_scaled(3), e.g. 512M.

- **console** *domain*

  Using [cu(1)](/cu/1.md) connect to the console of the guest domain.

- **delete** *configuration*

  Delete the specified configuration from non-volatile storage.

- **download** *directory*

  Save a logical domain configuration to non-volatile storage on the service processor. The name of the configuration is taken from the name of the *directory* which must contain files created with the **init-system** command. The download is aborted if a configuration with the same name already exists. Depending on the firmware, the new configuration must be activated explicitly using the **select** command.

- **dump**

  Dump the current configuration from non-volatile storage into the current working directory.

- **init-system** \[**-n**\] *file*

  Generate files in the current working directory for a logical domain configuration *file* as described in [ldom.conf(5)](/ldom.conf/5.md).

  - **-n**

    Configtest mode. Only check the configuration file for validity.

- **list**

  List configurations stored in non-volatile storage. Indicate the currently running configuration, and the configuration which will be used next (after resetting the machine) if it differs from the currently running one.

- **list-io**

  List available PCIe devices for the configuration in the current directory.

- **panic** \[**-c**\] *domain*

  Panic a guest domain. The exact behaviour of this command depends on the OS running in the domain. For OpenBSD the default behaviour is to enter [ddb(4)](/ddb/4.md).

  - **-c**

    Automatically connect to the guest console.

- **select** *configuration*

  Select the next logical domain configuration to use (after resetting the machine).

- **start** \[**-c**\] *domain*

  Start a guest domain.

  - **-c**

    Automatically connect to the guest console.

- **status** \[*domain*\]

  Display status information for *domain*, or for all domains running on the system.

- **stop** *domain*

  Stop a guest domain.

## EXAMPLES

A system using factory defaults has a single "factory-default" configuration:

```
# ldomctl list
factory-default [current]
```

Create a new configuration based on the defaults:

```
# mkdir factory-default
# cd factory-default
# ldomctl dump
# cd ..
# cp -R factory-default openbsd
# cd openbsd
```

A file describing the desired configuration must be created - see [ldom.conf(5)](/ldom.conf/5.md).

Generate a set of configuration files and download to non-volatile storage. If a configuration with the same name already exists, it must be removed first:

```
# ldomctl init-system ldom.conf
# cd ..
# ldomctl delete openbsd
# ldomctl download openbsd
# ldomctl list
factory-default [current]
openbsd [next]
```

Create a virtual disk image for each guest domain:

```
# ldomctl create-vdisk -s 8G /home/puffy/vdisk0
# ldomctl create-vdisk -s 8G /home/salmah/vdisk0
```

The minirootfs install media can be used to boot guest domains:

```
# cp miniroot67.img /home/puffy/vdisk1
# cp miniroot67.img /home/salmah/vdisk1
```

To have **ldomctl** enabled at boot time, use “rcctl enable ldomd”, which sets

```
ldomd_flags=""
```

in rc.conf.local(8).

Halt the primary domain and reset the hardware:

```
# halt
sc> reset -c	# ALOM
-> reset /SYS	# ILOM
```

The machine will now reset and boot into the new configuration. The primary domain should have less CPUs and memory, since they are now assigned to the guest domains:

```
# ldomctl status
primary     -         running     OpenBSD running                1%
puffy       ttyV0     running     OpenBoot Primary Boot Loader   8%
salmah      ttyV1     running     OpenBoot Primary Boot Loader  12%
```

Configure the [vnet(4)](/vnet/4.md) interfaces for the guest domains. This example bridges guest domains into the physical network:

```
# ifconfig vnet0 up
# ifconfig vnet1 up
# ifconfig bridge0 create
# ifconfig bridge0 add em0 add vnet0 add vnet1 up
```

Access the console of the first domain and boot it:

```
# ldomctl console puffy
Connected to /dev/ttyV0 (speed 9600)
{0} ok boot disk1
```

## SEE ALSO

[dd(1)](/dd/1.md), [ddb(4)](/ddb/4.md), [vnet(4)](/vnet/4.md), [ldom.conf(5)](/ldom.conf/5.md), [ldomd(8)](/ldomd/8.md)

## HISTORY

The **ldomctl** program first appeared in OpenBSD 5.3.

## AUTHORS

The **ldomctl** program was written by Mark Kettenis ⟨*kettenis@openbsd.org*⟩.