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diff --git a/doc/sources/azure/README.rst b/doc/sources/azure/README.rst deleted file mode 100644 index 8239d1fa..00000000 --- a/doc/sources/azure/README.rst +++ /dev/null @@ -1,134 +0,0 @@ -================ -Azure Datasource -================ - -This datasource finds metadata and user-data from the Azure cloud platform. - -Azure Platform --------------- -The azure cloud-platform provides initial data to an instance via an attached -CD formated in UDF. That CD contains a 'ovf-env.xml' file that provides some -information. Additional information is obtained via interaction with the -"endpoint". The ip address of the endpoint is advertised to the instance -inside of dhcp option 245. On ubuntu, that can be seen in -/var/lib/dhcp/dhclient.eth0.leases as a colon delimited hex value (example: -``option unknown-245 64:41:60:82;`` is 100.65.96.130) - -walinuxagent ------------- -In order to operate correctly, cloud-init needs walinuxagent to provide much -of the interaction with azure. In addition to "provisioning" code, walinux -does the following on the agent is a long running daemon that handles the -following things: -- generate a x509 certificate and send that to the endpoint - -waagent.conf config -~~~~~~~~~~~~~~~~~~~ -in order to use waagent.conf with cloud-init, the following settings are recommended. Other values can be changed or set to the defaults. - - :: - - # disabling provisioning turns off all 'Provisioning.*' function - Provisioning.Enabled=n - # this is currently not handled by cloud-init, so let walinuxagent do it. - ResourceDisk.Format=y - ResourceDisk.MountPoint=/mnt - - -Userdata --------- -Userdata is provided to cloud-init inside the ovf-env.xml file. Cloud-init -expects that user-data will be provided as base64 encoded value inside the -text child of a element named ``UserData`` or ``CustomData`` which is a direct -child of the ``LinuxProvisioningConfigurationSet`` (a sibling to ``UserName``) -If both ``UserData`` and ``CustomData`` are provided behavior is undefined on -which will be selected. - -In the example below, user-data provided is 'this is my userdata', and the -datasource config provided is ``{"agent_command": ["start", "walinuxagent"]}``. -That agent command will take affect as if it were specified in system config. - -Example: - -.. code:: - - <wa:ProvisioningSection> - <wa:Version>1.0</wa:Version> - <LinuxProvisioningConfigurationSet - xmlns="http://schemas.microsoft.com/windowsazure" - xmlns:i="http://www.w3.org/2001/XMLSchema-instance"> - <ConfigurationSetType>LinuxProvisioningConfiguration</ConfigurationSetType> - <HostName>myHost</HostName> - <UserName>myuser</UserName> - <UserPassword/> - <CustomData>dGhpcyBpcyBteSB1c2VyZGF0YQ===</CustomData> - <dscfg>eyJhZ2VudF9jb21tYW5kIjogWyJzdGFydCIsICJ3YWxpbnV4YWdlbnQiXX0=</dscfg> - <DisableSshPasswordAuthentication>true</DisableSshPasswordAuthentication> - <SSH> - <PublicKeys> - <PublicKey> - <Fingerprint>6BE7A7C3C8A8F4B123CCA5D0C2F1BE4CA7B63ED7</Fingerprint> - <Path>this-value-unused</Path> - </PublicKey> - </PublicKeys> - </SSH> - </LinuxProvisioningConfigurationSet> - </wa:ProvisioningSection> - -Configuration -------------- -Configuration for the datasource can be read from the system config's or set -via the `dscfg` entry in the `LinuxProvisioningConfigurationSet`. Content in -dscfg node is expected to be base64 encoded yaml content, and it will be -merged into the 'datasource: Azure' entry. - -The '``hostname_bounce: command``' entry can be either the literal string -'builtin' or a command to execute. The command will be invoked after the -hostname is set, and will have the 'interface' in its environment. If -``set_hostname`` is not true, then ``hostname_bounce`` will be ignored. - -An example might be: - command: ["sh", "-c", "killall dhclient; dhclient $interface"] - -.. code:: - - datasource: - agent_command - Azure: - agent_command: [service, walinuxagent, start] - set_hostname: True - hostname_bounce: - # the name of the interface to bounce - interface: eth0 - # policy can be 'on', 'off' or 'force' - policy: on - # the method 'bounce' command. - command: "builtin" - hostname_command: "hostname" - } - -hostname --------- -When the user launches an instance, they provide a hostname for that instance. -The hostname is provided to the instance in the ovf-env.xml file as -``HostName``. - -Whatever value the instance provides in its dhcp request will resolve in the -domain returned in the 'search' request. - -The interesting issue is that a generic image will already have a hostname -configured. The ubuntu cloud images have 'ubuntu' as the hostname of the -system, and the initial dhcp request on eth0 is not guaranteed to occur after -the datasource code has been run. So, on first boot, that initial value will -be sent in the dhcp request and *that* value will resolve. - -In order to make the ``HostName`` provided in the ovf-env.xml resolve, a -dhcp request must be made with the new value. Walinuxagent (in its current -version) handles this by polling the state of hostname and bouncing ('``ifdown -eth0; ifup eth0``' the network interface if it sees that a change has been -made. - -cloud-init handles this by setting the hostname in the DataSource's 'get_data' -method via '``hostname $HostName``', and then bouncing the interface. This -behavior can be configured or disabled in the datasource config. See -'Configuration' above. |