Network configuration for Arch instance in OpenStack

ezacaria · 2018-01-13 06:27:59

I have been trying to figure out the the simplest way to automatically configure the virtual network cards (vNICs) of an Arch instance in OpenStack.

I created my own image (booted an instance from an ISO9660 image into an empty volume) and configured a minimalistic system.
Now I would like have the network configuration be taken from the OpenStack metadata (e.g., via the "configDrive" as in "nova boot --config-drive=true") and applied without further manual intervention. I can, of course, log into the console and create netctl profiles by hand, but I would like to avoid doing this.

To illustrate the goal: one would launch an instance of the Arch image/snapshot with specific IP/subnets for 3 virtual NICs and the cloud-init would automatically configure them, e.g., via netctl.

After some fumbling with the sources, I managed to compile cloud-init 17.2 and run it. But the network configuration is not rendered.

I used different options in the cloud.cfg, but neither system_info/"distro: ubuntu" nor "distro: arch" worked. In case of the latter I get an error saying "apply_network_config is not currently implemented for distribution".

While it is true that I could inject the configuration files (via "nova --file") this would be redundant effort since the same information is already available via the OpenStack metadata.
Similarly, injecting netctl commands via the "user data" ("nova --user-data") is also requiring further effort from whomever is deploying the virtual machine.

We had some efforts in the past to use the cloud-init in Arch guests, e.g., https://bbs.archlinux.org/viewtopic.php?id=218370 and https://bbs.archlinux.org/viewtopic.php?id=170086, but we are not at a stage where it works "out of the box".

Now to more specific questions:

Is there an Arch development effort to provide Arch-specific implementation for the cloud-init functionality such as "apply_network_config"?
Since the Arch cloud-init package has recently disappeared from the repositories, does it mean that using it in OpenStack instances is discouraged? If so, what is the recommended mechanism to automatically configure the Arch instances?

Thanks!

Lone_Wolf · 2018-01-13 15:11:46

Is there an Arch development effort to provide Arch-specific implementation for the cloud-init functionality such as "apply_network_config"?

archlinux doesn't have a standard network management tool, any implementation that supports iproute2 should be fine.

Since the Arch cloud-init package has recently disappeared from the repositories, does it mean that using it in OpenStack instances is discouraged? If so, what is the recommended mechanism to automatically configure the Arch instances?

The cloud-init pacakge was moved from repositories to AUR because no TU or dev was wiling to maintain it.
Usability has no relevance to that decision.

using iproute2 commands seems best option.

ezacaria · 2018-01-17 05:19:11

Thanks for the prompt answer.

I agree that there would be ways to make it work. However, when looking at the list of outstanding bugs reported against the old package (and also based in my own experience), it is clear that it currently does not work in a variety of basic scenarios.

This begs the question: what is used in Arch images/instances in popular cloud services? Some opinions from the community would be useful here.

I imagine that most Arch users can configure the instance manually and may not bother to use cloud-init at all. However, the manual configuration would be inefficient if deploying many instances, or if intending the instance to be used by less technically minded users.

Just as a reference, the old package shows the following bugs that will not be fixed:

FS#53036
FS#54785
FS#54898
FS#54911

Arch Linux

#1 2018-01-13 06:27:59

Network configuration for Arch instance in OpenStack

#2 2018-01-13 15:11:46

Re: Network configuration for Arch instance in OpenStack

#3 2018-01-17 05:19:11

Re: Network configuration for Arch instance in OpenStack

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