From cOS Core version 13.00.08 onwards, the distributed KVM image is capable of providing Cloud-Init functionality for cOS Core instance initialization. cOS Core distributions for all virtual environments have Cloud-Init support enabled by default on startup. However, cOS Core will initialize with its default configuration if it is unable to retrieve the data for initialization from an external server.

External Cloud-Init Documentation

The full documentation for the Cloud-Init standard can be found at:

https://cloudinit.readthedocs.io/en/latest

Typical Configuration Actions Performed Using Cloud Init

Below is an example list of some of the typical configuration actions that the administrator might use Cloud-Init for prior to deploying an instance:

Prerequisites for Cloud-Init Setup

The following prerequisites are required for the Cloud-Init process:

A Summary of Cloud-Init Instance Initialization

The following steps outline the process of Cloud-Init initialization for any cOS Core instance:

Instance Configuration Data Files

When cOS Core has a route to 169.254.169.254, it requests the following files from the address using HTTP GET requests and in the order they are listed below:

The following should be noted about the retrieval and processing of these files:

cOS Core Local Console Output

As the Cloud-Init initialization process progresses, cOS Core will output messages to the cOS Core local console to indicate the initialization states. For example, the following messages would be seen as the file network_data.json is successfully retrieved from the Cloud-Init server and processed:

Cloud init - Connecting to server 169.254.169.254:80
[Connected to 169.254.169.254:80]
[Received 193 bytes from 169.254.169.254:80]
[Received 1460 bytes from 169.254.169.254:80]
[Received 269 bytes from 169.254.169.254:80]
TCP_EventHandler total bytes 1922
[Closing connection to 169.254.169.254:80...]
[6][Connection to 169.254.169.254:80 closed. (Normal close)]
[INFO] Parsed network data.
[INFO] Validated network data syntax.
[INFO] Network data successfully added to configuration.

A similar set of messages is then displayed as each of the other two files, meta_data.json and user_data, are retrieved and processed.

When, all available files have been successfully processed and the configuration changes completed, a cOS Core reconfigure operation is performed automatically to activate the changes. When this is complete, the following local console message appears to indicate successful instance initialization:

 Changes done by CLOUD INIT committed
[INFO] Cloud Init provisioning mode exit.

If one of the initialization files is not available, this will be indicated by local console output similar to the following, which is for a missing network_data.json file:

[INFO] No network data found in received file.
Will use default configuration.

If there are any errors retrieved in the received files, these will be highlighted. The following local console output related to an error found in a MAC address in the network_data.json file:

[ERROR] No match found for MAC '10:00:00:c6:15:f2'
referenced by interface 'if3_OK'.
[ERROR] Failed to update system with network data configuration.

Such errors will mean that any changes must be activated manually and the Cloud-Init process will end with the local console message:

[ERROR] There are errors in the received configuration.

Configuration File Examples

Below are examples of the three types of configuration files.

{
  "services": [
    {
      "type": "dns",
      "address": "123.123.123.123"
    },
    {
      "type": "dns",
      "address": "123.123.123.124"
    }
  ],
  "networks": [
    {
      "network_id": "some_id_1",
      "type": "ipv4_dhcp",
      "link": "some_link",
      "id": "network1"
    },
    {
      "network_id": "some_id_2",
      "type": "ipv4",
      "link": "some_link2",
      "id": "network2"
      "ip_address":"FFFF:0000:ABCD:0000:0300:0123:0123:0123",
      "netmask":"ffff:ffff:ffff:ffff:ffff:0:0:0"
    },
     {
      "network_id": "some_id_3",
      "type": "ipv4",
      "link": "some_link2",
      "id": "network2_ip4",
      "ip_address":"123.123.123.123",
      "netmask":"255.255.255.0"
    }
  ],
  "links": [
    {
      "type": "ovs",
      "vif_id": "some_vif_id",
      "ethernet_mac_address": "aa:aa:aa:aa:aa:aa",
      "id": "some_link",
      "mtu": 1500
    },
    {
      "type": "ovs",
      "vif_id": "some_vif_id_2",
      "ethernet_mac_address": "bb:bb:bb:bb:bb:bb",
      "id": "some_link2",
      "mtu": 1500
    }
  ]
}

A more extensive network_data.json example can be found at this link:

https://docs.openstack.org/nova/latest/_downloads/9119ca7ac90aa2990e762c08baea3a36/network_data.json

{
  "name": "MyCloudInstance001",
  "admin_pass": "aStrongPassword121!@",
  "public_keys":
    {
      "firstkey": "ecdsa-sha2-nistp521 AAAAB3NzaC1yc2EAAAABJQAAAQEAsn...",
      "secondkey": "ecdsa-sha2-nistp521 AAAAB3NzaC1yc2EAAAABJQAAAQEAl6...",
    }
}

Additional examples of both this and the network_data.json files can be found at this link:

https://docs.openstack.org/nova/latest/user/metadata.html#openstack-format-metadata

#cli-config
set Settings MiscSettings EnforceStrongPasswords=YES
add IPPolicy SourceInterface=If1 DestinationInterface=any
SourceNetwork=If1_net DestinationNetwork=all-nets
Service=all_services Name=allow_all Action=Allow

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