---
title: "VPC FAQ"
description: "Short answers about TIR VPCs, their address ranges, limits, and which machines can use them, each linking to the full page."
content_type: "faq"
product: "tir-vpc"
platform: "TIR"
url: "/tir/tir-vpc/faq/"
---

# VPC FAQ

## I created a VPC but cannot reserve an IP in it. Why?

A VPC you create under **Networking** > **VPC** is for virtual machines on a CPU plan. A reserved IP of
**Type** Private, also called a VPC IP, comes from a VPC in your E2E MyAccount project. See [VPCs](/tir/tir-vpc/concepts/vpcs/) and [Reserved IPs](/tir/tir-reserved-ip/concepts/reserved-ips/).

## Which machines can use a VPC?

Virtual machines on a CPU plan in Delhi and Chennai can use a VPC. To give a GPU instance or an inference service a private address,
reserve an IP of **Type** Private from a VPC in your E2E MyAccount project. See
[VPCs](/tir/tir-vpc/concepts/vpcs/#what-can-use-a-vpc) and [Reserved IPs](/tir/tir-reserved-ip/concepts/reserved-ips/).

## Can a VPC span regions?

No. A VPC belongs to one project in one region. See [VPCs](/tir/tir-vpc/concepts/vpcs/).

## Can I change the address range of a VPC?

No. You set the range when you create the VPC, and after that you can change only the name. If you need a
larger range, create a new VPC with one. See [VPC address ranges](/tir/tir-vpc/concepts/vpc-address-ranges/).

## How many VPCs can I have?

Your account can have five VPCs in each region, counted across all its projects. Support can raise the limit. See
[VPCs](/tir/tir-vpc/concepts/vpcs/#how-many-you-can-have).

## Does attaching a VPC restart my VM?

Yes. Attaching, switching, or detaching a VPC restarts the VM, so save your work first. A VM holds one VPC at
a time. See [Attach a VPC to a VM](/tir/tir-vm/how-to/attach-a-vpc-to-a-vm/).

## Can I share a VPC between projects?

No. A VPC belongs to one project in one region. Create a VPC in each project that needs one.

## Can two VPCs use the same address range?

Yes. Each VPC is a network of its own, and its traffic stays apart from every other VPC, even one with the
same range.

## Can I use a range inside 10.0.0.0/8?

No. Use a range inside 172.16.0.0 to 172.29.255.255 or inside 192.168.0.0/16. A VPC refuses 10.0.0.0/8,
172.30.0.0/16, and 172.31.0.0/16. See [VPC address ranges](/tir/tir-vpc/concepts/vpc-address-ranges/).

## Why does my VPC have nine fewer addresses than its range?

Every VPC sets aside its first eight addresses and its last one for networking. A `/24` gives 247 addresses
to your machines. See [Reserved addresses](/tir/tir-vpc/concepts/vpc-address-ranges/#reserved-addresses).

## Can I name my VPC default?

No. Every project has a default VPC that TIR manages and keeps off the list, so the name `default` is
reserved in any mix of upper and lower case.

## Is a VPC charged?

A VPC is free. See [VPCs](/tir/tir-vpc/concepts/vpcs/#billing).