Chapter 7 TCP/IP Configuration and Administrative Basics
- Configuration Files
- Symbolic Machine Names: /etc/hosts [alternative to Yellow Pages(YP), Network Information Services (NIS), and Domain Name Service (DNS)]
==>ex. 127.0.0.1 localhost local this_server
- Network Names: /etc/networks [used to resolve network names]
==>ex. loopback 127 localhost
- Network Protocols: /etc/protocols used to identify all the transport protocols available on the system and their respective protocol numbers [maintained by the system]
==>ex. ip 0 IP # internet protocol, pseudo protocol number
- Network Services: /etc/services - identifies exixting network services [maintained by the system]
==>ex. ftp 21/tcp
- Setting the Hostname
- $ hostname returns the hostname of the computer in UNIX
- $ hostname -S mycomputer.nmhu.edu can change the hostname in LINUX
- on Windows computers, use Networks in Control Panel to change the hostname
- The Loopback Driver internal virtual circuit (127.0.0.1)
- Managing ARP - administrator can create, modify, & delete entries in the arp table
- Using ifconfig - used to activate/deactivate and configure network interfaces
- ipconfig ec0 - returns information about ethernet card 0
- ifconfig interface_type IP_Address
- route - displays the current contents of the kernel's routing table
- route add|del IP_Address - add/removes routes in the kernel's routing table
- The inetd Daemon - used to handle port connections creating a process for each connection; uses /etc/inetd.cfg which contains service name, socket type, and protocol name, etc.
- The netstat Command - provides comprehensive information about the local system and its TCP/IP implementation
- Communications End Points [netstat -a - provides information on all active communications end points]
- Network Interface Statistics [netstat -i - provides information about the network interface]
- Data Buffers [netstat -m - provides information about the data buffers]
- Routing Table Information[netstat -r and netstat -rs - provides information about the routing tables
- Protocol Statistics [netstat -s - provides information about network protocols]
- The ping Utility - used to query another system to ensure that a connection is still active [sends out an ICMP echo request]
- Tracing a Connection - [tracert or trpt (trace report)]
