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Transfer Client IP Address (Dedicated Load Balancers)

Transfer Client IP Address

If you enable Transfer Client IP Address, your load balancer will use the IP address of the client to access the backend server.

Table 1 lists whether you can enable or disable the transfer client IP address function.

Table 1 Transfer client IP address

Listener Type	Enabling Transfer Client IP Address	Disabling Transfer Client IP Address
TCP and UDP	Enabled by default	×
HTTP and HTTPS	Enabled by default	×

Constraints

• If you enable Transfer Client IP Address, a server cannot be used as both the client and the backend server.

  If the client and the backend server are using the same server and the Transfer Client IP Address option is enabled, the backend server will think the packet is sent by itself but not from the client and will not return a response packet to the load balancer. As a result, the return traffic will be interrupted.

• After this function is enabled, unidirectional download or push traffic may be interrupted when backend servers are being migrated. After the backend servers are migrated, retransmit the packets to restore the traffic.
• If you add IP addresses as backend servers, the source IP addresses of the clients cannot be passed to these servers.

Alternatives for Obtaining the IP Address of the Client

You can obtain the IP address of a client in one of the ways listed in Table 2.

Table 2 Alternatives

Listener Type	Alternatives
TCP and UDP	N/A
HTTP and HTTPS	Layer 7 Load Balancing

Parent topic: Listener