Chapter 2. TCP/IP: Operation, Management, and AdvancedTopicsThis chapter discusses managing your network by using the NETSTAT command,and the maintenance of host tables. In addition, this chapter covers other topicsbeyond those that are required to configure and use TCP/IP on iSeries 400. Thisinformation may help you to understand and maximize your usage of the iSeriesTCP/IP support.TCP/IP on an iSeries server can also be managed by Simple Network ManagementProtocol (SNMP). For information about SNMP, see resources in the InformationCenter: Supplemental Manuals.Network StatusThe network status function on the server allows you to get information about thestatus of TCP/IP network interfaces, routes, and connections on your local system.This function also allows you to end TCP/IP connections and to start or endTCP/IP interfaces.Note: Network status functions may also be administered by OperationsNavigator. Use the Operations Navigator interface for these functions if it isinstalled on your system. See the Operations Navigator(http://www.as400.ibm.com/oper_nav/index.htm) Web page for moreinformation.NETSTAT displays the current TCP/IP protocol stack information. Thisinformation does not necessarily match the configuration data you see when usingthe Configure TCP/IP (CFGTCP) menu. In most cases, the NETSTAT commanddisplays more information than the configuration data. In some cases, theconfiguration data might even change.The reason for such a change is that the iSeries TCP/IP dynamically creates someinformation, such as *DIRECT routes, when TCP/IP starts. A change may alsooccur if the configuration data that was sent to TCP/IP when it starts is changeddynamically by TCP/IP applications that run after you start TCP/IP. Several typesof processing alter the initial TCP/IP configuration:v Internet Control Message Protocol (ICMP) requestsv Sockets ioctl system callsv Simple Network Management Protocol (SNMP) requestsv iSeries TCP/IP internal processingWork with TCP/IP Network Status MenuThe Work with TCP/IP Network Status menu allows you to work with the variousnetwork status functions.To display the Work with TCP/IP Network Status menu, take these steps:1. Type the WRKTCPSTS (Work with TCP/IP Network Status) command or theNETSTAT (Network Status) command.2. Press the Enter key. (See Figure 24 on page 34.)© Copyright IBM Corp. 1997, 2001 33
