Dynamic cloudinit network config [FEATURE REQUEST]

encryptblockr

We can create multiple VMs from cloud image template by dynamically setting hostnames

BUT how do we also apply setting synamic IP addresses to these VMs???

so that way can have something like this

test-1 -> static ipv4 192.168.1.5
test-2 -> static ipv4 192.168.1.6
test-3 -> static ipv4 192.168.1.7

in xen-orchestra we only can apply dynamic hostnames, but we can not apply dynamic static ip

dj423

@encryptblockr

FWIW: I know I have done this from cli using xo-cli in a bash script.

I don't have all that code handy at the moment, but here is a hack from memory as an example:

#! /bin/bash

while IFS=',' read -r name_c1 ip_c2
do
    file=v1-$ip_c2.yaml

    cat >> "$file" << EOF
network:
  version: 1
  config:
    - type: physical
      name: eth0
      subnets:
        - type: static
          address: $ip_c2/24
          gateway: 192.168.0.1
    - type: nameserver
      address:
        - 192.168.0.10
        - 192.168.23.50
      search:
        - example.tld
EOF

xo-cli vm.create bootAfterCreate=true cloudConfig="$(cat /root/user.yaml)" networkConfig="$(cat $file)" clone=true name_label="$name_c1" template=0856a8d6-7761-f39d-f968-290b18a1bd42 VIFs='json:[{"network":"ca96456f-3843-26f5-7075-1e54xxxx121xxf97"}]' hvmBootFirmware=bios copyHostBiosStrings=true

rm $file
done <  prov-list
exit

prov-list example:

Bookworm,192.168.0.217
Noble1,192.168.0.218
Jammy1,192.168.0.219
Oracle9,192.168.0.222
Rocky9,192.168.0.223
Fedora40,192.168.0.224

If you wanted to do different networks, that is a bit more complicated, but just need a variable to render.

Sorry on my tablet and I don't have a better example handy. But this should get you close, and can be handy when you need to stand up a few dozen VM's.

encryptblockr

@dj423 really cool

for now i decided to create one at a time
but when i get some will look into what you have above

thanks again!!!

olivierlambert

@julien-f I think we isolated Cloudinit variable from XO variable so we couldn't use XO variable in Cloudinit to do numbering, right?

julien-f

@olivierlambert It's still possible to use the VM number in the cloud-init template: {index} since XO 5.100 (% before)

See the changelog.

olivierlambert

So it could be a solution

dj423

@julien-f

Would that be something like this for a dynamic network config as an example?

network:
  version: 1
  config:
    - type: physical
      name: enX0
      subnets:
        - type: static
          address: 192.168.99.{index}/24
          gateway: 192.168.99.1
    - type: nameserver
      address:
        - 172.31.31.1
        - 192.168.45.11
      search:
        - example.tld

I plan to test this at some point, but I don't do a whole lot of bulk provisioning myself. Just curious.