Chapter 4

Administering TCP/IP (Task)

TCP/IP administration involves the procedures that you use to configure your network. First you assemble the hardware. Then you configure TCP/IP. This chapter explains how to configure TCP/IP. This chapter also addresses how to troubleshoot TCP/IP problems.

This chapter contains the following information:

• "Before You Configure TCP/IP"

• "Determining Host Configuration Modes"

• "Adding a Subnet to a Network Task Map"

• "Network Configuration Procedures"

• "Network Configuration Task Map"

• "Configuring Standard TCP/IP Services"

• "Configuring Routers"

• "Configuring Routers Task Map"

• "Creating a Multihomed Host"

• "Turning On Space-Saving Mode"

• "Turning Off ICMP Router Discovery"

• "Turning Off ICMP Router Discovery Task Map"

• "General Troubleshooting Tips"

• "Running Software Checks"

• "ping Command"

• "ping Command Task Map"

• "ifconfig Command"

• "ifconfig Command Task Map"

• "netstat Command"

• "netstat Command Task Map"

• "Logging Network Problems"

• "Displaying Packet Contents"

• "Displaying Packet Contents Task Map"

• "Displaying Routing Information"

Before You Configure TCP/IP

Before you configure TCP/IP, complete the tasks that are listed in the following table.

Table 4-1 Before You Configure TCP/IP Task Map

Description	For Instructions, Go To ...
Design the network topology.	See "Network Topology".
Obtain a network number from your Internet addressing authority.	See "Designing Your IPv4 Addressing Scheme".
Assemble the network hardware depending on the network topology. Assure that the hardware is functioning properly.	See the hardware manuals and "Network Topology".
Run configuration software that is required by network interfaces and routers, if applicable.	See "Adding Routers" and "Configuring Routers" for information on routers.
Plan the IP addressing scheme for the network. If applicable, include subnet addressing.	See "Designing Your IPv4 Addressing Scheme" and "IPv6 Addressing".
Assign IP numbers and host names to all machines in the network.	See "Designing Your IPv4 Addressing Scheme" and "IPv6 Addressing".
Determine which name service your network uses: NIS, NIS+, DNS, or local files.	See System Administration Guide: Naming and Directory Services (DNS, NIS, and LDAP) and System Administration Guide: Naming and Directory Services (FNS and NIS+).
Select domain names for your network, if applicable.	See System Administration Guide: Naming and Directory Services (DNS, NIS, and LDAP) and System Administration Guide: Naming and Directory Services (FNS and NIS+).
Install the operating system on at least one machine on the network.	See Solaris 9 Installation Guide.

Determining Host Configuration Modes

As a network administrator, you configure TCP/IP to run on hosts and routers (if applicable). You can configure these machines to obtain configuration information from files on the local machine or from files that are located on other machines on the network. You need the following configuration information:

• Host name of a machine

• IP address of the machine

• Domain name to which the machine belongs

• Default router

• Netmask in use on the machine's network (if applicable)

A machine that obtains TCP/IP configuration information from local files operates in local files mode. A machine that obtains TCP/IP configuration information from a remote machine operates in network client mode.