This topic provides answers to some frequently asked questions about DNAT.

How many DNAT entries can I add to a NAT gateway?

By default, you can add up to 100 DNAT entries to a NAT gateway.

If you want to increase the quota, go to the Quota Management page. For more information, see Manage quotas.

Why am I unable to find an existing EIP from the list of public IP addresses when I create a DNAT entry?

Before you create a DNAT entry, make sure that a NAT gateway is created and associated with an elastic IP address (EIP). For more information, see Configure DNAT to provide Internet-facing services.

Can I create DNAT entries for ECS instances that are assigned EIPs?

No, you cannot create DNAT entries for Elastic Compute Service (ECS) instances that are assigned EIPs.

Before you can create DNAT entries for these ECS instances, you must disassociate the EIPs from the ECS instances. For more information, see Disassociate an EIP from a cloud resource and Configure DNAT to provide Internet-facing services.
Note If you create DNAT entries for ECS instances that are assigned EIPs, the ECS instances preferentially use the EIPs to communicate with the Internet.