# Create a Subnet

## Overview <a href="#createasubnet-overview" id="createasubnet-overview"></a>

A subnet is a unique CIDR block with a range of IP addresses in a VPC. All resources in a VPC must be deployed on subnets.

* By default, all instances in different subnets of the same VPC can communicate with each other. If you have a VPC with two subnets in it, they can communicate with each other by default.
* After a subnet is created, its CIDR block cannot be modified. Subnets in the same VPC cannot overlap.
* When creating a **GPU VM**, an active **Subnet** in the VPC is required. The system will automatically assign a **Private IP** from that subnet to the new virtual machine.

## Step-by-Step <a href="#createasubnet-step-by-step" id="createasubnet-step-by-step"></a>

{% stepper %}
{% step %}
In the left-side menu, go to **Networking → Subnets**, then click **Create Subnet**.

<figure><img src="/files/tBhZMPMm4ih58O4HZSo1" alt=""><figcaption></figcaption></figure>

<figure><img src="/files/YvpBZjPfyWgfWoMQvlrE" alt=""><figcaption></figcaption></figure>
{% endstep %}

{% step %}
Enter a **name** for your subnet in the **Name** field.
{% endstep %}

{% step %}
Select the type of subne&#x74;**.** We currently support two types:

* **Routed**: The subnet is routed to the internet via a NAT gateway.
* **Isolated**: The subnet has no internet routing.
  {% endstep %}

{% step %}
Specify the IP range (subnet) your network will use, in CIDR notation (e.g. 172.30.65.0/24) using **Network Address (CIDR).**
{% endstep %}

{% step %}
Specify the IP address of the default gateway within your subnet using **Gateway IP**. This is usually the first usable IP (e.g. `172.30.65.1`).
{% endstep %}

{% step %}
Define a **Static IP Pool** — a specific range of IPs reserved for static assignments
{% endstep %}

{% step %}
Configure **DNS** Settings:

Specify the IP address of DNS servers that network clients will use to resolve domain names.&#x20;

* **Primary DNS**: Required DNS server for domain name resolution.
* **Secondary DNS (optional)**: Backup DNS server if the primary fails.
  {% endstep %}

{% step %}
Assign a **Tag** to categorize or organize your subnet.
{% endstep %}
{% endstepper %}


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