Basic customization with Cloud-init

[MichalTill]

Newbie question: I have a working bash script that creates a Cloud-init'ed VM via bunch of `qm` and `virt-customize` commands. Now I would like to customize the final state via Cloud-init YAML file (users, packages, files etc.). Beacause I am new to Proxmox and CI, I totally struggle with where to put the YAML file on the guest machine. Some examples operate with `/etc/cloud/cloud.cfg`, some with `snippets/vendor.yaml`, some with other places. I googled CI docs through and through, but fail to grasp this simple thing - where the YAML config (configs?) go.

Can you please point me to the right direction and what in bash script should I do with a YAML file so it gets processed by Cloud-init and machine is set accordingly?

 

[bbgeek17]

I totally struggle with where to put the YAML file on the guest machine

You dont generally "put" the file on guest machine. You feed the file via a method available in your cloud. For PVE its via "cicustom" (man qm).

`/etc/cloud/cloud.cfg`

This is a default location of generic Cloud Image that you can download from one of the Linux Vendors. This is where OS defaults are stored. Certainly, if you are building your Image from scratch - you can put as many common default variables there as you want.

with `snippets/vendor.yaml`

"snippets" is a PVE terminology. It's a location where you can put various configuration files.

By default, you can place them in /var/lib/vz/snippets (https://pve.proxmox.com/wiki/Storage:_Directory)
Or, if you have other FILE-based storage - you can place it there. Of course, you have to mark that storage pool as "available for snippets", as well as create an appropriate directory structure.

YML files placed in that structure must be specified via "cicustom" and will be fed via special ISO to your VM during boot.
Normally, you would place any customization there that is above your default config.

Note, that the procedure above is PROXMOX specific. Other clouds/hypervisors will operate differently.

https://pve.proxmox.com/wiki/Cloud-Init_Support

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Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox

 

[MichalTill]

You dont generally "put" the file on guest machine. You feed the file via a method available in your cloud. For PVE its via "cicustom" (man qm).

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Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox

Aha! So my my script will put the config yaml to /var/lib/vz/snippets/vendor.yaml, which is in fact local:snippets/vendor.yaml and it is fed with

qm set $VMID --cicustom "vendor=local:snippets/vendor.yaml"

?

 

[MichalTill]

This is a default location of generic Cloud Image that you can download from one of the Linux Vendors. This is where OS defaults are stored. Certainly, if you are building your Image from scratch - you can put as many common default variables there as you want.

Then, what does this in general do? Exactly what config is this?

echo "### Copying Proxmox Cloud-init config to image ###"
virt-customize -a $DISK_IMAGE --upload ${CURRENT_DIR}/cloud.cfg:/etc/cloud/cloud.cfg

 

[bbgeek17]

?

yes

Then, what does this in general do? Exactly what config is this?

Why not download one of the Cloud images from (Ubuntu, Debian, Rocky, Almalinux, etc) and examine it?

Or plug it into search and examine pages such as:
https://docs.redhat.com/en/document...init-configuration_introduction-to-cloud-init

Or check github?
https://github.com/canonical/cloud-init/tree/main/config

Good luck

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Blockbridge : Ultra low latency all-NVME shared storage for Proxmox - https://www.blockbridge.com/proxmox