Comment 4 for bug 1869291

I'm not sure this configuration you suggest will work, I don't see any documentation that suggests you can put the autoinstall.yaml file on a secondary device.

In any case, providing an iso with CIDATA as a label is going to trigger cloud-init to attempt to use this iso as a datasource.

Your autoinstall.yaml is not a valid cloud-init datasource. I suspect that's why nothing is happening in your autoinstall method.

You could construct your autoinstall file with 'cloud-localds', like so:

cat >user-data <<EOF
#cloud-config
autoinstall:
    version: 1
    early-commands:
        - ls -al
    locale: en_US
    keyboard:
        layout: en
        variant: uk
    proxy: http://proxy.vmware.com:3128/
    storage:
        layout:
            name: lvm
    identity:
        realname: zouy
        hostname: ubuntu
        username: vmware
        password: ca$hc0w
EOF
echo "instance-id: $(uuidgen || echo i-abcdefg)" > meta-data
cloud-localds seed.iso user-data metadata

The contents of the iso are:
seed.iso
/user-data
/meta-data

cloud-image-utils provides cloud-localds

Then you can attach that iso and should allow subiquity to pickup the
autoinstall config.