az network vnet list-available-ips: Add total count metadata for capacity planning

[UnXpectedSparkWorker]

Describe the bug

Command Name
az network vnet list-available-ips

Issue:
The command only returns a limited list of available IPs (appears to be first 5 available) without providing the total count of available IPs or indicating that the response is truncated.

Related Issues

This builds on previously closed issues (#25427, #13853) which focused on listing more IPs. However, this request is specifically for metadata (total count) rather than an exhaustive list, which serves different operational use cases.

To Reproduce:

• Create a VNet with a /24 subnet (should have ~248 available IPs after Azure reservations for platform usage)
• Run az network vnet list-available-ips --ids <vnet-resource-id>
• Observe that only 5 IPs are returned despite many more being available

Expected Behavior

The API response should include:

1. Total count of available IPs - essential for capacity planning and monitoring
2. Clear indication if the list is truncated - so users know there are more IPs available
3. Optional pagination or limit parameters - to control response size

Suggested response format:

{
  "totalAvailableIPs": 247,
  "availableIPs": ["10.0.0.4", "10.0.0.5", "..."],
  "truncated": true
}

Environment Summary

Linux-5.15.167.4-microsoft-standard-WSL2-x86_64-with-glibc2.39, Ubuntu 24.04.2 LTS
Python 3.12.8
Installer: DEB

azure-cli 2.71.0 *

Additional Context

[azure-client-tools-bot-prd]

Hi @UnXpectedSparkWorker,

2.71.0 is not the latest Azure CLI(2.75.0).

If you haven't already attempted to do so, please upgrade to the latest Azure CLI version by following https://learn.microsoft.com/en-us/cli/azure/update-azure-cli.

[yonzhan]

Thank you for opening this issue, we will look into it.

[UnXpectedSparkWorker]

Hi @UnXpectedSparkWorker,

2.71.0 is not the latest Azure CLI(2.75.0).

If you haven't already attempted to do so, please upgrade to the latest Azure CLI version by following https://learn.microsoft.com/en-us/cli/azure/update-azure-cli.

I've upgraded to Azure CLI version 2.75.0-1~noble and can confirm the same behavior persists:

$ az --version
azure-cli                         2.75.0

$ az network vnet list-available-ips --ids <vnet-resource-id>
[
  "10.0.0.4",
  "10.0.0.5",
  "10.0.0.6",
  "10.0.0.7",
  "10.0.0.8"
]

[UnXpectedSparkWorker]

Thank you for opening this issue, we will look into it.

@yonzhan Thanks for the quick response!

To clarify - I'd like this metadata (total count + truncation indicator) available for both VNet and subnet levels, since both commands have the same limitation:

• az network vnet list-available-ips (VNet level)
• az network vnet subnet list-available-ips (subnet level)

In my specific use case, I was using the subnet level command (az network vnet subnet list-available-ips) for capacity monitoring of individual subnets, but the same operational need applies at both levels.

For DataOps workflows, we need to monitor capacity at both:

• Subnet level: Track utilization of specific subnets for capacity planning
• VNet level: Overall network capacity across the entire VNet

Both commands currently return only a sample of available IPs without indicating how many total IPs are available, making capacity monitoring difficult.