Overview of the LB Layer4 tab

The LB Layer4 tab configures the IPVS component of the Linux Virtual Server (LVS) project. This load balancer is provided for TCP and UDP load balancing applications. It supports DSR Direct Server Return, destination NAT, and IPIP tunnels.

The LVS layer 4 load balancer routes TCP or UDP traffic to the backend servers.

Configured in NAT mode, LVS provides destination NAT. If source NAT is also desired, use the NAT tab to configure it.

LVS by itself either listens to all ports on an IP or a single specified port. If you need to listen on a range of ports, define a flow.

LVS supports a variety of configurable options such as:

• Load balancing schemes including round robin, least connection, source, destination, source/destination, and shortest expected delay.
• Server health checks by HTTP, TCP, ICMP, or ARP protocol.