Web OS 10.0 Application GuideChapter 6: Server Load Balancing n 139212777-A, February 2002Mapping PortsAn Alteon Web switch allows you to hide the identity of a port for security by mapping a vir-tual server port to a different real server port.Mapping a Virtual Server Port to a Real Server PortIn addition to providing direct real server access in some situations (see “Mapping Ports” onpage 144), mapping is required when administrators choose to execute their real server pro-cesses on different ports than the well-known TCP/UDP ports. Otherwise, virtual server portsare mapped directly to real server ports by default and require no mapping configuration.Port mapping is configured from the Virtual Server Services menu. For example, to map thevirtual server TCP/UDP port 80 to real server TCP/UDP port 8004, you could enter the follow-ing:N OTE – If filtering is enabled, a proxy IP address is configured, or URL parsing is enabled onany switch port, then port mapping is supported with Direct Access Mode (DAM). For infor-mation about DAM, refer to “Using Direct Access Mode” on page 143.Mapping a Single Virtual Server Port to Multiple Real Server PortsTo take advantage of multi-CPU or multi-process servers, Web OS can be configured to map asingle virtual port to multiple real ports. This capability allows the Web site managers, forexample, to differentiate users of a service by using multiple service ports to process clientrequests.An Alteon Web switch supports up to 16 real ports per server when multiple rports areenabled. This feature allows the network administrator to configure up to 16 real ports for asingle service port. This feature is supported in Layer 4 and Layer 7 and in cookie-based andSSL persistence switching environments.When multiple real ports on each real server are mapped to a virtual port, the Web switch treatsthe real server IP address/port mapping combination as a distinct real server.N OTE – For each real server, you can only configure one service with multiple real ports.>> # /cfg/slb/virt 1/service 80 (Select virtual server port 80)>> Virtual Server 1 http Service# rport 8004 (Map to real port 8004)
