Azure Network Interface
Does ZopNight manage Azure Network Interface?
Azure network interfaces are free (a NIC itself never appears on an invoice), but each NIC is the join record linking a VM to its subnet, VNet, NSG, and public IP. ZopNight discovers NICs via Resource Graph to build that graph, and orphaned NICs left after VM deletion signal leftover plumbing.
Rules that fire on Azure Network Interface
No active rule family targets Azure Network Interface today. Rules that used to are retired, and retired rules publish no pages and fire no findings. Scheduling and permissions coverage are unaffected.
At a glance
| Field | Value |
|---|---|
| Scheduling notes | discovery and topology only. |
Network interfaces (NICs) connect VMs to subnets and carry IP configurations. NICs are free but are the join between compute and network topology.
A NIC never bills, its attachments do
There is no meter on a network interface. What a NIC carries, however, frequently does bill: a public IP attached to one of its IP configurations charges hourly, and accelerated networking ties the NIC to VM sizes with their own rates. More importantly for cost work, the NIC is where Azure records which VM sits in which subnet, so nearly every question of the form “what else is on this network segment” resolves through NIC data.
The join record between compute and network
Discovered via Azure Resource Graph and used to link VMs to subnets, VNets, NSGs, and public IPs in the topology graph. This linkage is load-bearing: NIC join data is what enables VNet placement of VMs, noted as a current enrichment gap. Where the join is incomplete, a VM is known but its network position is not. NICs themselves are discovery and topology only; scheduling acts on the VM, and the NIC simply persists across every deallocate and start cycle, keeping its private IP configuration intact.
Orphaned NICs after VM deletion
Deleting a VM does not automatically delete its network interfaces. The detached NIC lingers, and while it costs nothing directly, it often keeps two billable things alive: a static public IP still bound to its IP configuration, and by implication the impression that an environment is still in use. A subscription with hundreds of detached NICs is describing its own history of deleted machines, and each one is worth checking for an attached IP before cleanup. NICs reserved for a planned deployment that never happened show the same signature from the other direction.
NIC lists in the Azure portal
Azure portal → Network interfaces shows every NIC with its attached VM (blank for orphans), private IP, and associated NSG. Filtering for interfaces with no attached virtual machine surfaces the detached population in one view, the manual version of the join-and-filter ZopNight runs continuously.