Configuring the WSM using Device Manager

Direct server return health checking  

Direct Server Return (DSR) health checking verifies the existence of a server service where the server replies directly back to the client without responding through the virtual server IP address.

The server is configured with a real server IP address and virtual server IP address. The virtual server IP address is configured to be the same address as the user's virtual server IP address. When DSR health checking is configured, the health check is sent originating from one of the WSM's configured IP interfaces, and is destined to the virtual server IP address with the MAC address that was acquired from the real server IP address's Address Resolution Protocol (ARP) entry.

The WSM verifies that the server correctly responds to requests made to the virtual server IP address as required in DSR configurations. To perform this function, the real server IP address is replaced with the virtual server IP address in the health check packets that are forwarded to the real servers for health checking. With this feature enabled, the health check will fail if the real server is not properly configured with the virtual server IP address.

See also:

• About direct server return
• Configuring DSR health checks
• ICMP health checking
• ARP health checking
• Link health checking
• TCP health checking
• Script-based health checking
• Modifying the health check interval and retries
• Application health checking
• About health checking