AutoInstall - Cloud-Init setup using nocloud datasource

[alex]

I am trying to setup a number of new servers on Ubuntu 20.4 LTS. So far 
I
got the auto-install via PXE working.

My plan is to use autoinstall for the basic setup to install the OS,
partition table and initial user.

Once installed I was hoping to use something like clout-init / nocloud 
to
install the customisation need to security and monitoring. Ideally I was
just hoping to connect it to chef using cloud-init.

However I have not been able to get cloud-init / nocloud-net datasource
working.

Tried updating /etc/default/grub with the following

GRUB_DEFAULT=0
#GRUB_TIMEOUT_STYLE=hidden
GRUB_TIMEOUT=30
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="serial=ds=nocloud-net;seedfrom=http://192.168.
0.172/ubuntu/config/"
GRUB_CMDLINE_LINUX="serial=ds=nocloud-net;seedfrom=http://192.168.0.172/ub
untu/config/"

Any suggestions to get me in the right direction on how to get 
nocloud-net working?

No matter what I try it always reports:

root at ubuntu-base:/home/user# cloud-init status --long
status: done
time: Wed, 06 Jan 2021 09:53:14 +0000
detail:
DataSourceNone

And the httpd host which provides the configuration files is never
accessed.

Kind regards
Alex