Configuration tools

• /etc/sysconfig/network - Defines your network and some of its characteristics.
• /etc/HOSTNAME - Shows the host name of this host. IF your name is "myhost" then that is exactly the text this file will contain.
• /etc/resolv.conf - Specifies the domain to be searched for host names to connect to, the nameserver address, and the search order for the nameservers.
• /etc/host.conf - Specifies the order nameservice looks to resolve names.
• /etc/hosts - Shows addresses and names of local hosts.
• /etc/networks - Provides a database of network names with network addresses similar to the /etc/hosts file. This file is not required for operation.
• /etc/sysconfig/network-scripts/ifcfg-eth* - There is a file for each network interface. This file contains the IP address of the interface and many other setup variables.

Analysis Tools

• netstat - Displays information about the systems network connections, including port connections, routing tables, and more. The command "netstar -r" will display the routing table.
• traceroute - This command can be used to determine the network route from your computer to some other computer on your network or the internet. To use it you can type "route IPaddress" of the computer you want to see the route to.
• nslookup - Used to query DNS servers for information about hosts.
• arp - This program lets the user read or modify their arp cache.
• tcpdump - This program allows the user to see TCP traffic on their network.
• dig(1) - Send domain name query packets to name servers for debugging or testing