Networking fundamentals

Question 1

Network Config files:

/etc/hosts

Answer 1

• always contains the localhost IP address, 127.0.0.1
• Sometimes contains addresses of additional hosts

Sample output:

Do not remove the following line, or various programs

that require network functionality will fail.

127. 0.0.1 localhost.localdomain localhost
128. 168.52.10 tux.mylan.com tux
129. 168.52.11 winxp.mylan.com winxp

Question 2

Network Config files:

/etc/resolv.conf

Answer 2

• configures access to a DNS server

Sample output:

search mylan.com

nameserver 193.134.20.4

Question 3

Network Config files:

/etc/nsswitch.conf

Answer 3

• defines the order in which to contact different name services

Sample output:

[bob@tux ~] grep hosts /etc/nsswitch.conf

hosts: files dns

Question 4

Network Config command:

ip command

Answer 4

• assigning IP addresses to interfaces
• for setting up routes to the Internet and to other networks
• displaying TCP/IP configurations etcetera

eg.

ip addr show

ip route show

Question 5

Network Config command:

ifconfig command

Answer 5

• configure a network interface

(preferable using ip command)

Question 6

Network checking command:

netstat command

Answer 6

• Print network connections, routing tables, interface statistics, masquerade connections, and multi‐
  cast memberships

Question 7

Network checking command:

host command

Answer 7

• display information on hosts or domains

Question 8

Network checking command:

ping command

Answer 8

• check if a host is alive

Question 9

Network checking command:

traceroute / tracepath command

Answer 9

• check the route that packets follow to a network host