VMware#
This datasource is for use with systems running on a VMware platform such as vSphere and currently supports the following data transports:
The configuration method is dependent upon the transport.
Guest OS customization#
The following configuration can be set for this datasource in cloud-init
configuration (in /etc/cloud/cloud.cfg or
/etc/cloud/cloud.cfg.d/).
System configuration#
disable_vmware_customization: true (disable) or false (enable) the VMware traditional Linux guest customization. Traditional Linux guest customization is customizing a Linux virtual machine with a traditional Linux customization specification. Setting this configuration to false is required to make sure this datasource is found inds-identifywhen using Guest OS customization transport. VMware Tools only checks this configuration in/etc/cloud/cloud.cfg.Default: true
Datasource configuration#
allow_raw_data: true (enable) or false (disable) the VMware customization usingcloud-initmetadata and user data directly. Since vSphere 7.0 Update 3 version, users can create a Linux customization specification with minimalcloud-initmetadata and user data, and apply this specification to a virtual machine. This datasource will parse the metadata and user data and configure the virtual machine with them. See Guest customization using cloud-init for more information.Default: true
vmware_cust_file_max_wait: The maximum amount of clock time (in seconds) that should be spent waiting for VMware customization files.Default: 15
Configuration examples#
Enable VMware customization and set the maximum waiting time for the VMware customization file to 10 seconds:
Set
disable_vmware_customizationin the/etc/cloud/cloud.cfgdisable_vmware_customization: false
Create a
/etc/cloud/cloud.cfg.d/99-vmware-guest-customization.cfgwith the following contentdatasource: VMware: vmware_cust_file_max_wait: 10
Enable VMware customization but only try to apply a traditional Linux Guest Customization configuration, and set the maximum waiting time for the VMware customization file to 10 seconds:
Set
disable_vmware_customizationin the/etc/cloud/cloud.cfgdisable_vmware_customization: false
Create a
/etc/cloud/cloud.cfg.d/99-vmware-guest-customization.cfgwith the following contentdatasource: VMware: allow_raw_data: false vmware_cust_file_max_wait: 10
VMware Tools configuration#
VMware Tools is required for this datasource’s configuration settings, as well as vCloud and vSphere admin configuration. Users can change the VMware Tools configuration options with the following command:
vmware-toolbox-cmd config set <section> <key> <value>
The following VMware Tools configuration option affects this datasource’s behaviour when applying customization configuration with custom scripts:
[deploypkg] enable-custom-scripts: If this option is absent in VMware Tools configuration, the custom script is disabled by default for security reasons. Some VMware products could change this default behaviour (for example: enabled by default) via customization of the specification settings.VMware admins can refer to customization configuration and set the customization specification settings.
For more information, see VMware vSphere Product Documentation and specific VMware Tools configuration options.
GuestInfo keys#
One method of providing meta, user, and vendor data is by setting the following
key/value pairs on a VM’s extraConfig property:
Property |
Description |
|---|---|
|
A YAML or JSON document containing the |
|
The encoding type for |
|
A YAML document containing the |
|
The encoding type for |
|
A YAML document containing the |
|
The encoding type for |
All guestinfo.*.encoding values may be set to base64 or
gzip+base64.
Features#
This section reviews several features available in this datasource.
Graceful rpctool fallback#
The datasource initially attempts to use the program vmware-rpctool if it
is available. However, if the program returns a non-zero exit code, then the
datasource falls back to using the program vmtoolsd with the --cmd
argument.
On some older versions of ESXi and open-vm-tools, the vmware-rpctool
program is much more performant than vmtoolsd. While this gap was
closed, it is not reasonable to expect the guest where cloud-init is running to
know whether the underlying hypervisor has the patch.
Additionally, vSphere VMs may have the following present in their VMX file:
guest_rpc.rpci.auth.cmd.info-set = "TRUE"
guest_rpc.rpci.auth.cmd.info-get = "TRUE"
The above configuration causes the vmware-rpctool command to return a
non-zero exit code with the error message Permission denied. If this should
occur, the datasource falls back to using vmtoolsd.
Instance data and lazy networks#
One of the hallmarks of cloud-init is
its use of instance-data and JINJA queries – the
ability to write queries in user and vendor data that reference runtime
information present in /run/cloud-init/instance-data.json. This works
well when the metadata provides all of the information up front, such as the
network configuration. For systems that rely on DHCP, however, this
information may not be available when the metadata is persisted to disk.
This datasource ensures that even if the instance is using DHCP to configure
networking, the same details about the configured network are available in
/run/cloud-init/instance-data.json as if static networking was used.
This information collected at runtime is easy to demonstrate by executing the
datasource on the command line. From the root of this repository, run the
following command:
PYTHONPATH="$(pwd)" python3 cloudinit/sources/DataSourceVMware.py
The above command will result in output similar to the below JSON:
{
"hostname": "akutz.localhost",
"local-hostname": "akutz.localhost",
"local-ipv4": "192.168.0.188",
"local_hostname": "akutz.localhost",
"network": {
"config": {
"dhcp": true
},
"interfaces": {
"by-ipv4": {
"172.0.0.2": {
"netmask": "255.255.255.255",
"peer": "172.0.0.2"
},
"192.168.0.188": {
"broadcast": "192.168.0.255",
"mac": "64:4b:f0:18:9a:21",
"netmask": "255.255.255.0"
}
},
"by-ipv6": {
"fd8e:d25e:c5b6:1:1f5:b2fd:8973:22f2": {
"flags": 208,
"mac": "64:4b:f0:18:9a:21",
"netmask": "ffff:ffff:ffff:ffff::/64"
}
},
"by-mac": {
"64:4b:f0:18:9a:21": {
"ipv4": [
{
"addr": "192.168.0.188",
"broadcast": "192.168.0.255",
"netmask": "255.255.255.0"
}
],
"ipv6": [
{
"addr": "fd8e:d25e:c5b6:1:1f5:b2fd:8973:22f2",
"flags": 208,
"netmask": "ffff:ffff:ffff:ffff::/64"
}
]
},
"ac:de:48:00:11:22": {
"ipv6": []
}
}
}
},
"wait-on-network": {
"ipv4": true,
"ipv6": "false"
}
}
Redacting sensitive information (GuestInfo keys transport only)#
Sometimes the cloud-init user data might contain sensitive information,
and it may be desirable to have the guestinfo.userdata key (or other
guestinfo keys) redacted as soon as its data is read by the datasource.
This is possible by adding the following to the metadata:
redact: # formerly named cleanup-guestinfo, which will also work
- userdata
- vendordata
When the above snippet is added to the metadata, the datasource will iterate
over the elements in the redact array and clear each of the keys. For
example, when the guestinfo transport is used, the above snippet will cause
the following commands to be executed:
vmware-rpctool "info-set guestinfo.userdata ---"
vmware-rpctool "info-set guestinfo.userdata.encoding "
vmware-rpctool "info-set guestinfo.vendordata ---"
vmware-rpctool "info-set guestinfo.vendordata.encoding "
Please note that keys are set to the valid YAML string --- as it is not
possible remove an existing key from the guestinfo key-space. A key’s
analogous encoding property will be set to a single white-space character,
causing the datasource to treat the actual key value as plain-text, thereby
loading it as an empty YAML doc (hence the aforementioned ---).
Reading the local IP addresses#
This datasource automatically discovers the local IPv4 and IPv6 addresses for
a guest operating system based on the default routes. However, when inspecting
a VM externally, it’s not possible to know what the default IP address is for
the guest OS. That’s why this datasource sets the discovered, local IPv4 and
IPv6 addresses back in the guestinfo namespace as the following keys:
guestinfo.local-ipv4guestinfo.local-ipv6
It is possible that a host may not have any default, local IP addresses. It’s also possible the reported, local addresses are link-local addresses. But these two keys may be used to discover what this datasource determined were the local IPv4 and IPv6 addresses for a host.
Waiting on the network#
Sometimes cloud-init may bring up the network, but it will not finish
coming online before the datasource’s setup function is called, resulting
in a /var/run/cloud-init/instance-data.json file that does not have the
correct network information. It is possible to instruct the datasource to wait
until an IPv4 or IPv6 address is available before writing the instance data
with the following metadata properties:
wait-on-network:
ipv4: true
ipv6: true
If either of the above values are true, then the datasource will sleep for a second, check the network status, and repeat until one or both addresses from the specified families are available.
Walkthrough of GuestInfo keys transport#
The following series of steps is a demonstration of how to configure a VM with this datasource using the GuestInfo keys transport:
Create the metadata file for the VM. Save the following YAML to a file named
metadata.yaml:instance-id: cloud-vm local-hostname: cloud-vm network: version: 2 ethernets: nics: match: name: ens* dhcp4: yes
Create the userdata file
userdata.yaml:#cloud-config users: - default - name: akutz primary_group: akutz sudo: ALL=(ALL) NOPASSWD:ALL groups: sudo, wheel lock_passwd: true ssh_authorized_keys: - ssh-rsa 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 [email protected]
Please note this step requires that the VM be powered off. All of the commands below use the VMware CLI tool, govc.
Go ahead and assign the path to the VM to the environment variable
VM:export VM="/inventory/path/to/the/vm"
Power off the VM:
⚠️ First Boot ModeTo ensure the next power-on operation results in a first-boot scenario for
cloud-init, it may be necessary to run the following command just before powering off the VM:cloud-init clean --logs --machine-id
Otherwise
cloud-initmay not run in first-boot mode. For more information on how the boot mode is determined, please see the First Boot Documentation.govc vm.power -off "${VM}"
Export the environment variables that contain the
cloud-initmetadata and user data:export METADATA=$(gzip -c9 <metadata.yaml | { base64 -w0 2>/dev/null || base64; }) \ USERDATA=$(gzip -c9 <userdata.yaml | { base64 -w0 2>/dev/null || base64; })
Assign the metadata and user data to the VM:
govc vm.change -vm "${VM}" \ -e guestinfo.metadata="${METADATA}" \ -e guestinfo.metadata.encoding="gzip+base64" \ -e guestinfo.userdata="${USERDATA}" \ -e guestinfo.userdata.encoding="gzip+base64"
Note
Please note the above commands include specifying the encoding for the properties. This is important as it informs the datasource how to decode the data for
cloud-init. Valid values formetadata.encodinganduserdata.encodinginclude:base64gzip+base64
Power on the VM:
govc vm.power -on "${VM}"
If all went according to plan, the CentOS box is:
Locked down, allowing SSH access only for the user in the user data.
Configured for a dynamic IP address via DHCP.
Has a hostname of
cloud-vm.
Examples of common configurations#
Setting the hostname#
The hostname is set by way of the metadata key local-hostname.
Setting the instance ID#
The instance ID may be set by way of the metadata key instance-id. However,
if this value is absent then the instance ID is read from the file
/sys/class/dmi/id/product_uuid.
Providing public SSH keys#
The public SSH keys may be set by way of the metadata key public-keys-data.
Each newline-terminated string will be interpreted as a separate SSH public
key, which will be placed in distro’s default user’s
~/.ssh/authorized_keys. If the value is empty or absent, then nothing
will be written to ~/.ssh/authorized_keys.
Configuring the network#
The network is configured by setting the metadata key network with a value
consistent with Network Config Version 1 or
Version 2, depending on the Linux distro’s version
of cloud-init.
The metadata key network.encoding may be used to indicate the format of
the metadata key network. Valid encodings are base64 and
gzip+base64.