Enabling Public Network Access for an ECS

Binding an EIP

Suitable for public network access in temporary or dynamic changes or specific scenarios.

• Backend servers need to be frequently replaced or services need to be redeployed in temporary test environment, development environment, or demonstration environment.
• Fast failover: If an ECS is faulty, you can quickly unbind the EIP from the faulty ECS and bind it to the standby ECS to minimize service interruption.
• If multiple ECSs are added, the IP address for providing services externally needs to remain unchanged.
• On a single ECS, multiple services that require independent public IP addresses to provide services externally are deployed.

• An EIP is a public IP address that can be purchased and held independently.
• It can be dynamically unbound from or bound to ECSs.
• Compared with other methods, EIPs are flexible and easy to manage.

Binding an EIP

Network address translation using NAT Gateway

Suitable for scenarios where an EIP is shared by multiple ECSs

The SNAT function provided by the NAT Gateway service allows the ECSs in a VPC to access the Internet without requiring an EIP. Additionally, SNAT supports a large number of concurrent connections for applications that have a large number of requests and connections.

Can an ECS Without an EIP Bound Access the Internet?

Using ELB to distribute incoming traffic from public networks

Suitable for load balancing and distributing incoming traffic from public networks

After an EIP is bound to a private network load balancer, the load balancer becomes a public network load balancer. Clients can access backend servers through this load balancer over Internet.

For more information, see ELB Function Overview.

• Using ELB to Distribute Traffic to a Web Application Across ECSs
• Using ELB to Distribute Traffic to Multiple Web Applications Across ECSs

Assigning an IPv6 address with EIP bandwidth enabled

Suitable for applications or services that support IPv6

Compared with IPv4, IPv6 provides sufficient network addresses and more advanced network features. You can use IPv6 addresses to access public networks.

• Enabling IPv6 for a Network Interface
• Binding an EIP

Using ELB to distribute incoming traffic from public networks

Suitable for load balancing and distributing incoming traffic from public networks

After an EIP is bound to a private network load balancer, the load balancer becomes a public network load balancer. Clients can access backend servers through this load balancer over Internet.

For more information, see ELB Function Overview.

• Creating a Dedicated Load Balancer
• Does ELB Support IPv6 Networks?