ISO deploy causes unwanted isolated guest network creation even when L2 network is selected #11227
Description
problem
When deploying a VM using an ISO image, CloudStack automatically creates an isolated guest network using the default offering DefaultIsolatedNetworkOfferingWithSourceNatService — even though an L2 network is explicitly selected during deployment.
In a clean system, this behavior doesn't happen and the selected L2 network is honored without creating a new one.
After comparing the configurations of two identical CloudStack environments (one working, one problematic), we found extra or differing entries in network_offering_details — particularly involving parameters like internetProtocol, domainid, etc.
This seems to trigger the system into thinking it needs a network with DHCP capabilities, which leads to the automatic L3 network creation.
versions
CloudStack version: 4.20.1.0
Hypervisor: VMware
The steps to reproduce the bug
- Log in to the CloudStack UI.
- Navigate to “ISO” and register or select an existing ISO image (e.g., Ubuntu 20.04 or Windows Server 2022).
- Go to “Instances” and click “Deploy VM”.
- Select a custom offering, disk offering, and in the Network step, choose an existing L2 Guest Network (not isolated).
- Complete the wizard and click “Launch VM”.
- Observe that CloudStack automatically creates an Isolated Guest Network (L3) using the offering
DefaultIsolatedNetworkOfferingWithSourceNatService. - The VM NIC is attached to the newly created L3 network instead of the selected L2 network.
What to do about it?
No response