# Add Backend Servers to a Listener

Backend servers receive traffic forwarded by the listener. You can configure backend servers in one of the following ways:

* **By Instance**: Select backend servers directly from existing elastic compute instances.
* **By IP Address**: Manually specify backend server IP addresses.

After the listener is created, you can add backend servers to the listener by going to the listener list page and selecting **Actions** > **Add Backend Server**.

<div align="left" data-with-frame="true"><figure><img src="/files/aKhfOplgsPC5cxbG3Age" alt="" width="563"><figcaption></figcaption></figure></div>

### By Instance

When adding backend servers by **Instance**, you select compute instances directly from the resource list. Backend services run on cloud instances and you can have a simpler, cloud-native management.

#### Instance

Select the elastic compute instance to add.

The instance and the load balancer must be in the same-region subnet under one global VPC.

#### Private IPv4

The private IP address of the elastic compute instance, used by the listener for request forwarding and health checks.

#### Port

The target port for request forwarding and health checks.

Specify only one port in the range from `1` to `65535`. If empty, it will follow the listening port configuration.

#### Weight

The proportion of requests allocated to each backend server. The higher the weight, the more requests the server will receive.

Weight ranges from `0` to `65535`, and the default weight is `100`. A weight of `0` means the server will not accept new requests.

Click **Add Backend Server** to add more backend servers.

### By IP Address

When adding backend servers by **Private IP**, you manually specify the private IP addresses of backend servers. Backend servers are identified **only by IP**. It is a more flexible and IP-based configuration.

#### Private IPv4

The private IP address of the elastic compute instance, used by the listener for request forwarding and health checks.

#### Port

The target port for request forwarding and health checks.

Specify only one port in the range from `1` to `65535`. If empty, it will follow the listening port configuration.

#### Weight

The proportion of requests allocated to each backend server. The higher the weight, the more requests the server will receive.

Weight ranges from `0` to `65535`, and the default weight is `100`. A weight of `0` means the server will not accept new requests.

Click **Add Private IPv4** to add more private IPv4 addresses.

{% hint style="success" %} <mark style="color:green;">**Hint**</mark>

<mark style="color:green;">You can also go to</mark> <mark style="color:green;">**Backend server list**</mark> <mark style="color:green;">></mark> <mark style="color:green;">**Actions**</mark> <mark style="color:green;">></mark> <mark style="color:green;">**Remove**</mark> <mark style="color:green;">on Details page to remove a backend server.</mark>
{% endhint %}


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