Proxmox get VM IP address is a pain when the guest agent isn’t installed or the VM uses DHCP. The GUI shows nothing and the docs are useless. Here’s what actually works.

Check the guest agent first
If the QEMU guest agent is running inside the VM, the IP shows up right in the Proxmox summary page. Enable it in the VM options and install the agent inside the guest. Done. But if the VM is a minimal install, a container, or some appliance that doesn’t have the agent, you’re stuck staring at a blank field. Annoying.
DHCP lease inspection
If your VM gets its IP from a DHCP server on your network (like your router or a Pi-hole), just look at the leases. On the Proxmox host, check the lease file:
cat /var/lib/dhcp/dhcpd.leases
Or if you’re using dnsmasq:
cat /var/lib/misc/dnsmasq.leases
Match the MAC address from the VM hardware tab. This is the easiest method when it works—no extra tools, no scanning. The catch? The lease file might be somewhere else depending on your setup, and if the VM has a static IP configured inside the guest, it won’t show up here at all.

ARP scanning
When DHCP doesn’t help, scan the subnet. Install arp-scan if you don’t have it:
apt install arp-scan
Then run it against your network:
arp-scan --localnet
You’ll get a list of IPs and MACs. Find the MAC from the VM hardware tab and you’ve got your IP. This works even with static IPs inside the guest, as long as the VM is talking on the network. If the VM just booted and hasn’t sent any traffic, it might not show up—ping the broadcast address first or just wait a bit.
What I’d do
For a homelab, just install the guest agent on every VM you spin up. It’s a one-time thing and saves you from this crap every time. If you can’t, keep arp-scan handy. The DHCP method is too hit-or-miss. And if you’re building a VM image, bake the agent in—here’s how to make a Proxmox VM image that already has it.