Layer 4 Forwarding (TCP/UDP)

Layer 4 forwarding works in the transmission layer of the OSI model. After the traffic is delivered from the client, it is forwarded to the application server by modifying the address information of the data packet.

Layer 7 Forwarding (HTTP/HTTPS)

Layer 7 forwarding will establish a complete connection with the client and resolve the request traffic of the application layer, and select an application server based on the scheduling algorithm.

Load Balance Algorithm

It supports round robin, weighted round robin, source address hash and least connections algorithms.

Load Balance Type

ESurfing Cloud provides WAN and Intranet LB.

Session Persistence

A user can enable the session persistence function for load balance service listeners. Cookie-based session persistence is provided for Layer 7 (HTTP) services and IP address-based session persistence is provided for Layer 4 (TCP) services.

Obtaining the Real IP of A User

For Layer 7 (HTTP) services, LB can obtain the real visitor IP through Http Header:X-Forwarded-For. For Layer 4 (TCP) services, a TOA plugin can be set to acquire the real visitor IP.

Traffic Distribution and Forwarding Policy

A user can select three traffic distribution modes including round robin, least connections and source address to configure a LB listener. The listener can configure a forwarding policy and support forwarding by domain name and URL. URL forwarding supports accurate matching, prefix matching and regular expression matching, helping users to flexibly and conveniently distribute traffic.

Health Check

Users can specify a health check method and frequency. LB regularly checks whether the backend ECS runs properly based on the preset health check rules. Once it detects that ECS is unhealthy, access traffic will not be distributed to the instances on the unhealthy ECS.

DR Across Availability Zones

Backend service nodes in different availability zones can be bound to achieve cross-AZ DR.

IPv6

It supports an IPv4/IPv6 dual-stack scheme.

Elastic Load Balancing

Functions