[docs]: apply_network_config: false config is not effect

[Liuwenfan]

Environment is such as:

Cloud-init: v23.1.1 platform: Azure OS: Rocky9.2

I need to set apply_network_config to false in config file: /etc/cloud/cloud.cfg, to disable change the way of create network config file(ifcfg-ethx), because when more than one ip in machine metadata，cloud-init in init-local step set other ip to static ip.

I change config first, such as

cat /etc/cloud/cloud.cfg
# .....
datasource:
  Azure:
    apply_network_config: false

then reboot virtual machine, I find it is not effect, I can find message from log, this log is added by myself

DataSourceAzure.py[DEBUG]: debug ds_cfg :{'data_dir': '/var/lib/waagent', 'disk_aliases': {'ephemeral0': '/dev/disk/cloud/azure_resource'}, 'apply_network_config': True}
......
handlers.py[DEBUG]: finish: azure-ds/generate_network_config_from_instance_network_metadata: SUCCESS: generate_network_config_from_instance_network_metadata

but I alse can see the config is loaded by program,

2024-03-08 07:35:45,046 - stages.py[DEBUG]:  debug _cfg: {'datasource_list': ['Azure', 'None'], 'datasource': {'Azure': {'apply_network_config': False}}......

I add some debug code in DataSourceAzure.py file

    @azure_ds_telemetry_reporter
    def _generate_network_config(self):
        """Generate network configuration according to configuration."""
        # Use IMDS network metadata, if configured.
        LOG.debug("debug _metadata_imds :%s",self._metadata_imds)
        LOG.debug("debug ds_cfg :%s",self.ds_cfg)
        if (
            self._metadata_imds
            and self._metadata_imds != sources.UNSET
            and self.ds_cfg.get("apply_network_config")
        ):
            try:
                return generate_network_config_from_instance_network_metadata(
                    self._metadata_imds["network"]
                )
            except Exception as e:
                LOG.error(
                    "Failed generating network config "
                    "from IMDS network metadata: %s",
                    str(e),
                )

        # Generate fallback configuration.
        try:
            return _generate_network_config_from_fallback_config()
        except Exception as e:
            LOG.error("Failed generating fallback network config: %s", str(e))

as you see, I want cloud-init generate network config content from _generate_network_config_from_fallback_config function, but the apply_network_config: false is not effect

[Liuwenfan]

I add some other test case, I change the config apply_network_config:false and sync the change to vm image. the config in new machine that create from this image take effect.

[CalvoM]

@Liuwenfan Quick question, do you run sudo cloud-init clean --logs after modifying the /etc/cloud/cloud.cfg file and before rebooting the VM?

[CalvoM]

I have followed the following steps:

1. Edit the /etc/cloud/cloud.cfg
2. Run sudo cloud-init clean --logs
3. Rebooted the VM I get the following the logs:

   2024-03-12 09:22:58,103 - handlers.py[DEBUG]: start: azure-ds/_generate_network_config: _generate_network_config
   2024-03-12 09:22:58,103 - handlers.py[DEBUG]: start: azure-ds/_generate_network_config_from_fallback_config: _generate_network_config_from_fallback_config
   2024-03-12 09:22:58,107 - handlers.py[DEBUG]: finish: azure-ds/_generate_network_config_from_fallback_config: SUCCESS: _generate_network_config_from_fallback_config
   2024-03-12 09:22:58,107 - handlers.py[DEBUG]: finish: azure-ds/_generate_network_config: SUCCESS: _generate_network_config
   2024-03-12 09:23:59,112 - handlers.py[DEBUG]: start: azure-ds/_generate_network_config: _generate_network_config
   2024-03-12 09:23:59,112 - handlers.py[DEBUG]: start: azure-ds/_generate_network_config_from_fallback_config: _generate_network_config_from_fallback_config
   2024-03-12 09:23:59,113 - handlers.py[DEBUG]: finish: azure-ds/_generate_network_config_from_fallback_config: SUCCESS: _generate_network_config_from_fallback_config
   2024-03-12 09:23:59,113 - handlers.py[DEBUG]: finish: azure-ds/_generate_network_config: SUCCESS: _generate_network_config

   I see it generates the network config from fallback config.

[Liuwenfan]

old config is apply_network_config:true? I have changed the config value to false in image; I change the value to true in machine which default value of apply_network_config is false and effect, then run cloud-init clean command, command return status is zero. after machine reboot, I get following logs:

2024-03-13 05:35:31,539+0000 - handlers.py[DEBUG]: finish: azure-ds/_generate_network_config_from_fallback_config: SUCCESS: _generate_network_config_from_fallback_config 

the desired result is generate_network_config_from_instance_network_metadata, the current apply_network_config is true

[CalvoM]

Hey @Liuwenfan I have tried reproducing this

Rocky 9.3 Cloud-init v23.1.1 platform Azure

However I have not been successful.

1. When the apply_network_config is True this is what I get

   2024-03-13 09:16:12,045 - handlers.py[DEBUG]: start: azure-ds/_generate_network_config: _generate_network_config
   2024-03-13 09:16:12,045 - handlers.py[DEBUG]: start: azure-ds/generate_network_config_from_instance_network_metadata: generate_network_config_from_instance_network_metadata
   2024-03-13 09:16:12,048 - handlers.py[DEBUG]: finish: azure-ds/generate_network_config_from_instance_network_metadata: SUCCESS: generate_network_config_from_instance_network_metadata
   2024-03-13 09:16:12,049 - handlers.py[DEBUG]: finish: azure-ds/_generate_network_config: SUCCESS: _generate_network_config
   2024-03-13 09:17:12,952 - handlers.py[DEBUG]: start: azure-ds/_generate_network_config: _generate_network_config
   2024-03-13 09:17:12,952 - handlers.py[DEBUG]: start: azure-ds/generate_network_config_from_instance_network_metadata: generate_network_config_from_instance_network_metadata
   2024-03-13 09:17:12,954 - handlers.py[DEBUG]: finish: azure-ds/generate_network_config_from_instance_network_metadata: SUCCESS: generate_network_config_from_instance_network_metadata
   2024-03-13 09:17:12,954 - handlers.py[DEBUG]: finish: azure-ds/_generate_network_config: SUCCESS: _generate_network_config

2. I change the value to false
3. Run sudo cloud-init clean --logs
4. Reboot vm
5. Checking the logs later I get

   2024-03-15 13:15:01,608 - handlers.py[DEBUG]: start: azure-ds/_generate_network_config: _generate_network_config
   2024-03-15 13:15:01,608 - handlers.py[DEBUG]: start: azure-ds/_generate_network_config_from_fallback_config: _generate_network_config_from_fallback_config
   2024-03-15 13:15:01,609 - handlers.py[DEBUG]: finish: azure-ds/_generate_network_config_from_fallback_config: SUCCESS: _generate_network_config_from_fallback_config
   2024-03-15 13:15:01,609 - handlers.py[DEBUG]: finish: azure-ds/_generate_network_config: SUCCESS: _generate_network_config
   2024-03-15 13:16:02,540 - handlers.py[DEBUG]: start: azure-ds/_generate_network_config: _generate_network_config
   2024-03-15 13:16:02,541 - handlers.py[DEBUG]: start: azure-ds/_generate_network_config_from_fallback_config: _generate_network_config_from_fallback_config
   2024-03-15 13:16:02,542 - handlers.py[DEBUG]: finish: azure-ds/_generate_network_config_from_fallback_config: SUCCESS: _generate_network_config_from_fallback_config
   2024-03-15 13:16:02,542 - handlers.py[DEBUG]: finish: azure-ds/_generate_network_config: SUCCESS: _generate_network_config

[aciba90]

Thanks, @Liuwenfan, for reporting this.

I am unable to reproduce your issue. In my end, if apply_network_config is set to true, then generate_network_config_from_instance_network_metadata is executed and if set to false, then _generate_network_config_from_fallback_config and that is the expected behavior.

Could you please attach the [logs](sudo cloud-init collect-logs) of one of your instances, without any modification of cloud-init source code, and explain what is the behavior you expect?