Chapter 8 - Configuring Basic Networking Flashcards
Describe the information needed to configure a computer on a static IP network.
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Four pieces of information are important: the IP address, the netmask (network mask or subnet mask), the network’s gateway address and the address of at least one DNS server. The first two are required, but if you omit either or both of the latter two, basic networking will function, but you won’t be able to connect to the Internet or use most DNS hostnames
Determine when using /etc/hosts rather than DNS makes the most sense.
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The /etc/hosts file provides a static mapping of hostsnames to IP addresses on a single computer. Therefore, maintaining this file on a handful of computers for a small local network is fairly straightforward, but when the number of computers rises beyond a few or when IP addresses change frequently, running a DNS server to handle local name resolution make more sense.
Summarize tools you can use to translate between hostnames and IP addresses
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The nslookup program can perform these translations in both directions using either command line or interactive modes, but this program has been deprecated. You’re better off using host for simple lookups and dig for more complex tasks.
Describe the function of network ports
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Network ports enable packets to be directed to specific programs, each network-enable program attaches itself to one or more ports, sending data from that port and receiving data directed to the port. Certain ports are assigned to be used by specific servers, enabling client programs to contact servers by directing requests at specific port numbers on he server computers
Explain when you should use static IP addresses or DHCP
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Static IP address configuration involves manually entering the IP address and other information and is used when a network lacks a DHCP server or when a computer shouldn’t be configured by that server. DHCP configuration is easier to set up on the client bu works only if the network has a DHCP server system.
Explain what the route command accomplishes
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The route command displays or modifies the routing table, which tell Linux how to direct the packets on their destination IP address.
Describe some basic network diagnostic tools
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The ping program tests basic network connectivity and traceroute and tracepath perform similar but more complex tests that can help you localize where on a route between two systems a problem exists. The netstat utility is a general purpose network status tool that can report a wide variety of information about your network configuration. Packet sniffers such as tcdump provide detailed information about the network packets “seen” by a computer, which can be a useful way to verify that certain packet types are actually being sent or recieved
