META-DATA(8) - System Manager's Manual

NAME

meta-data - meta-data server for OpenBSD's virtual machine daemon

SYNOPSIS

meta-data [-23] [-u user] [-l lease-file] [bridge]

DESCRIPTION

The meta-data FastCGI program provides a cloud-init datasource for OpenBSD's vmd(8) that is compatible with Apache CloudStack and partially compatible with Amazon EC2.

The options are as follows:

-2

Run in layer 2 mode. meta-data will find the guest VM by its MAC address in the DHCP lease-file and the bridge cache. This is the default if layer 3 mode is not specified. The default bridge name is "bridge0".

-3

Run in layer 3 mode. meta-data will find the guest VM by its IPv4 address in the ARP table. The layer 2 and 3 modes can be combined.

-u user

Change the user name. The default is "_meta-data".

-l lease-file

Change the lease-file. The default is /var/db/dhcpd.leases.

Use the following steps to run meta-data:

Create the meta-data directory and add the "_meta-data" user:

# mkdir -p /home/vm/meta-data
# groupadd -g 787 _meta-data
# useradd -g 787 -u 787 -k /var/empty -d /home/vm/meta-data \
	-s /sbin/nologin -c "meta-data user" _meta-data

Use the kfcgi(8) FastCGI server to run meta-data. Start it as root, with chroot disabled, and meta-data will drop privileges by itself. The meta-data socket has to be owned by the "www" user of the web server.
```
# kfcgi -r -n 2 -u www -p / -- /usr/local/libexec/meta-data
```

Configure and start httpd(8) to handle meta-data requests:

server "meta-data" {
	listen on 169.254.169.254 port 80
	fastcgi socket "/run/httpd.sock"
	root { "/", strip 1 }
}

ATTRIBUTES

meta-data serves a number of attributes, so-called meta-data items and optional user-data, that are specific to the requesting VM. The following attributes are supported:

meta-data/availability-zone

This option is provided for compatibility. It includes the name of the bridge interface.

meta-data/instance-id

The VM identifier in the format vm‌ID, e.g. vm1.

meta-data/local-hostname

The hostname of the guest VM, based on the VM name that was specified in vm.conf(5) or by the vmctl(8) start command.

meta-data/local-ipv4

The IPv4 address of the guest VM. It is identical to the verified guest IP address of the HTTP request.

meta-data/public-hostname

This option is provided for compatibility. It includes the hostname of the vmd(8) host where meta-data is running.

meta-data/public-ipv4

This option is provided for compatibility. It currently includes the fixed string "127.0.0.1".

meta-data/public-keys/0/openssh-key

The SSH public key that is included in the openssh-key file in the VM's configuration directory. See the FILES section below. meta-data returns an "HTTP 404 Not Found" error if the file does not exist.

meta-data/service-offering

This option is provided for compatibility. It includes the fixed string "OpenBSD".

meta-data/username

Returns the contents of the username file in the VM's configuration directory, or "puffy" if it does not exist. This item is not available in other meta-data implementations.

user-data

Returns the contents of the user-data file in the VM's configuration directory, or an "HTTP 404 Not Found" if it does not exist. The user-data file typically includes a configuration file or shell script of a type that is indicated by the "shebang" in the first line, for example "#!/bin/sh" or "#cloud-config".

FILES

/home/vm/meta-data/openbsd.vm

Directory containing meta-data for the virtual machine "openbsd.vm".

openssh-key

The SSH public key in the VM's meta-data directory.

user-data

"user-data" file in the VM's meta-data directory.

username

The login username (this is an extension).

AUTHORS

Reyk Floeter <reyk@openbsd.org>

OpenBSD 6.1 - June 30, 2017