Chapter 12: Configuring Network Services and Cloud Technologies

Upon running the ifconfig command, the IP address is listed along with the subnet mask in dotted decimal notation listed as 255.255.255.224. You have installed a remote access software that has an address field that requires the address to be configured in CIDR notation. Which of the following is the equivalent CIDR notation for the subnet mask listed?

/27 Correct. 255.255.255.224 in dotted decimal notation is the same as /27 in CIDR notation.

Which of the following files does the hostnamectl command modify to set the hostname on a machine?

/etc/hostname Correct. The /etc/hostname file is configured with the hostname of the system.

Which of the following is a valid APIPA address?

169.254.38.101 Correct. The 169.254.0.0 through 169.254.255.255 range of IP addresses has been designated for use by the Automatic Private IP Address (APIPA) method of assigning IP addresses when a DHCP server is unavailable and an address has not been statically assigned.

The output of the ifconfig shows a HWaddr expressed in hexadecimal. How many bits is the hardware address shown made up of?

48 Correct. There are 48 bits in a hardware, or MAC, address.

Which of the following ports would be used to resolve a domain name to an IP address?

53 Correct. Port 53 is used by DNS, or the Domain Name System.

Wireless-Fidelity (Wi-Fi)

A LAN technology that uses Ethernet to transmit data over the air.

port

A number that uniquely identifies a network service.

True

SSH encrypts all traffic that passes across the network, whereas telnet does not. True or False?

False

Standalone daemons are started on demand using xinetd. True or False?

What is the most commonly used LAN protocol?

TCP/IP Correct. The Transmission Control Protocol/Internet Protocol (TCP/IP) provides a reliable communication of packets across the Internet. This is the most commonly used LAN protocol.

stand-alone daemons

The daemons that configure themselves at boot time without assistance from inetd or xinetd.

routers

The devices capable of transferring packets from one network to another. routing The act of forwarding data packets from one network to another.

True **?? /etc/sysconfig/network

The line that configures the host name for the computer at boot time can be found in /etc/hostname. True or False?

IP version 4 (IPv4)

The most common version of IP used on the Internet. It uses a 32-bit addressing scheme organized into different classes.

packets

The packages of data formatted by a network protocol.

You have set up a TFTP server to support PXE booting of several workstations. Which of the following protocols would this setup make use of?

UDP Correct. TFTP is a UDP based protocol. UDP is the User Datagram Protocol.

Which of the following can be used to graphically remotely administer a Linux machine?

VNC Correct. VNC is Virtual Network Computing and is a cross-platform method of graphically connecting to a remote system.

Putty

Which Windows program is often used to connect to a Linux server via SSH? Putty Rdesktop mstsc

Which of the following are valid statements in the /etc/resolv.conf file? (Choose two.)

domain comptia.org Correct. The domain statement is a valid statement in the /etc/resolv.conf file. nameserver 10.1.1.4

Which of the following commands will display detailed information for network hardware?

ethtool

Which of the following commands will show active UDP connections on a Linux system? (Choose all that apply.)

netstat --udp netstat -u Correct. The -u option for netstat will limit the results to UDP connections.

Which of the following commands will send 4 ICMP echo requests to a remote host named server1 to determine the round trip time it takes a packet to travel?

ping -c 4 server1

Which of the following commands can be used to trace an IPv6 route? (Choose two.)

tracepath6 traceroute6 Correct. The traceroute6 command can be used to trace an IPv6 route.

Virtual Network Computer (VNC)

A cross-platform technology that allows users to connect to a graphical desktop across a network.

wide area networks (WANs)

Networks in which computers are separated geographically by large distances.

host ID

The portion of an IP address that denotes the host.

network ID

The portion of an IP address that denotes the network.

nslookup hostname dig hostname host hostname

To test DNS configuration by resolving a host name to an IP address, which command or commands can you use? (Choose all that apply.) nslookup hostname dig hostname host hostname resolve hostname

ssh-keygen ssh-copy-id

You want to generate SSH keys for your user account and copy them to a remote computer to simplify future SSH authentication. What two commands can you use to perform these actions? (Choose two answers.) ssh-keygen ssh-add ssh-copy-id ssh-agent

You run the command hostname server1 and issue the reboot command. You notice that the host name has reverted back to what it was before the reboot. Which of the following commands should you have used to change the host name instead?

hostnamectl set-hostname server1 Correct. The hostnamectl command will change a Linux system's host name so that it persists across reboots.

Putty

A cross-platform SSH client.

local area networks (LANs)

Networks in which the computers are all in close physical proximity.

What is the complete path and filename of the file where ports and their associated protocols are defined? ___________

/etc/services

hostname command

A command used to display and change the host name of a computer.

modprobe command

A command used to insert a module into the Linux kernel.

lshw command

A command used to list details regarding hardware devices in a Linux system.

lsmod command

A command used to list the modules that are currently used by the Linux

VNC viewer

A program used to connect to a VNC server and obtain a graphical desktop.

Internet Control Message Protocol version 6 (ICMPv6)

A protocol used by computers to obtain an IPv6 configuration from a router on the network.

subnet mask

A series of four 8-bit numbers that determine the network and host portions of an IP address.

well-known ports

Of the 65,535 possible ports, the ports from 0 to 1024, which are used by common networking services.

DNS /etc/hosts

What are two means available to resolve a host name to the appropriate IP address? (Choose two answers.) DHCP DNS /etc/hosts /etc/resolve.conf

netstat -t

Which commands can be used to display TCP/IP connections on your Linux system? (Choose all that apply.) netstat -t mtr traceroute show ss -t

/etc/nsswitch.conf

Which file holds the methods to be used and the order in which they will be applied for host name resolution? /etc/nsswitch.conf /etc/resolve.conf /etc/hosts /etc/dns.conf

/etc/resolv.conf

Which file stores the IP addresses of the DNS servers used to resolve host names if no DNS servers are specified within the network configuration file for the network interface? /etc/hosts /etc/host.conf /etc/resolve /etc/resolv.conf

/etc/sysconfig/network-scripts/ifcfg-enp8s0

Which file would you modify to permanently change the IP address of a network interface on a Fedora 28 system? /etc/sysconfig/network-scripts/ifcfg-enp8s0 /etc/sysconfig/network /etc/netplan/50-cloud-init.yaml /etc/network/interfaces

Apache (httpd) DNS (named)

Which of the following are stand-alone daemons? (Choose all that apply.) Apache (httpd) Washington University FTP (in.ftpd) telnet (in.telnetd) DNS (named)

ssh -X VNC

Which of the following can be used to provide graphical remote administration? (Choose all that apply.) telnet ssh -X ssh VNC

22

Which of the following port numbers is associated with SSH? 22 137 49 23

ifconfig ping netstat -i

Which of the following utilities can be used to check TCP/IP configuration and test network connectivity? (Choose all that apply.) ifconfig iwconfig ping nmcli

route ip

Which two commands can be used to modify the route table on a Linux computer? (Choose two answers.) route ipconfig ip traceroute

octet

A portion of an IP address that represents eight binary bits. ping (Packet Internet Groper) command A command used to check TCP/IP connectivity on a network.

network service

A process that responds to network requests.

IP version 6 (IPv6)

A recent version of IP that is used by some hosts on the Internet. It uses a 128-bit addressing scheme.

Internet Protocol (IP) address

A series of four 8-bit numbers that represent a computer on a network.

protocol

A set of rules of communication used between computers on a network.

media access method

A system that defines how computers on a network share access to the physical medium.

route table

A table of information used to indicate which networks are connected to network interfaces.

Secure Shell (SSH)

A technology that can be used to run remote applications on a Linux computer; it encrypts all client-server traffic.

Network Address Translation (NAT)

A technology used on routers that allows computers on a network to obtain Internet resources via a single network interface on the router itself.

host name

A user-friendly name assigned to a computer.

Which of the following is the keyword that should be listed after the hosts statement in the /etc/nsswitch.conf file so that the system will consult the /etc/hosts file to resolve a name to an IP address?

files Correct. The files keyword should be listed after the hosts statement in the /etc/nsswitch.conf file in order for the system to consult the /etc/hosts file for name resolution.

Which of the following will display entries from the Name Service Switch libraries?

getent Correct. The getent command will display entries from the databases supported by the Name Service Switch libraries that are configured in /etc/nsswitch.conf.

User Datagram Protocol/Internet Protocol (UDP/IP)

A faster but unreliable version of TCP/IP.

Automatic Private IP Addressing (APIPA)

A feature that automatically configures a network interface using an IPv4 address on the 169.254.0.0 network.

Network Connections tool

A graphical utility in Fedora 20 that can be used to configure DSL settings.

Network utility

A graphical utility in Fedora 20 that can be used to configure network settings for the NICs on the system.

Modem Manager utility

A graphical utility that can be used to configure modem settings on Linux systems.

Domain Name Space (DNS)

A hierarchical namespace used for host names. Ethernet The most common media access method used in networks today.

fully qualified domain name (FQDN)

A host name that follows DNS convention.

Token Ring

A media access method commonly used by industrial networks.

Extended Internet Super Daemon (xinetd)

A network daemon that is used to start other network daemons on demand.

Internet Super Daemon (inetd)

A network daemon that is used to start other network daemons on demand.

Which of the following types of technologies will create a tunneled encrypted connection from a remote location into a corporate network to be able to access resources as if the user was physically connected to the LAN?

VPN Correct. A VPN is a Virtual Private Network. It allows remote users to tunnel across the public Internet while encrypting the traffic so the user can access resources as if they were physically on the LAN.

proxy server

A network server that accepts Internet requests from other computers on the same LAN and obtains the desired resource on their behalf.

classless interdomain routing (CIDR) notation

A notation that is often used to represent an IP address and its subnet mask.

traceroute6

A command used to trace the path an IPv6 packet takes through host.

Internet service provider (ISP)

A company that provides Internet access.

You currently have a Linux system configured to check the /etc/hosts file before trying to contact a DNS server to resolve host names. You want to reverse the configuration so that it checks with a DNS server before falling back to the /etc/hosts file. Which of the following files should you modify to make this possible?

/etc/nsswitch.conf

ssh command

A command that connects to a remote SSH daemon to perform remote administration.

hostnamectl command

A command used to change the host name of a computer as well as ensure that the new host name is loaded at boot time.

pppoe-setup command

A command used to configure a DSL connection on Fedora 20 systems.

pppoeconf command

A command used to configure a DSL connection on Ubuntu Server 14.04 systems.

ifconfig (interface configuration) command

A command used to display and modify the TCP/IP configuration information for a network interface.

insmod command

A command used to insert a module into the Linux kernel.

ip command

A command used to manipulate the route table.

route command

A command used to manipulate the route table.

whois command

A command used to obtain information about the organization that maintains a DNS domain.

rmmod command

A command used to remove a module from the Linux kernel.

telnet command

A command used to run remote applications on a Linux computer.

vncpasswd command

A command used to set a VNC password for a user.

nm-connection-editor command

A command used to start the Network Connections tool on Fedora 20 systems.

traceroute

A command used to trace the path an IPv4 packet takes through host.

tracepath command

A command used to trace the path an IPv4 packet takes through routers to a destination

tracepath6

A command used to trace the path an IPv6 packet takes through host.

default gateway

Before a computer can use a router, what configuration information must it be provided? routing table subnet mask default gateway default router

loopback address

The IP address of 127.0.0.1 is also referred to as the _____. local address lookup address local host loopback address

default gateway

The IP address of the router on the network used to send packets to remote networks.

False

The NetworkManager or Systemd-networkd components must be installed on a Linux system in order to configure an IP address on a network interface. True or False?

multicast

The TCP/IP communication destined for a certain group of computers.

unicast

The TCP/IP communication destined for a single computer.

broadcast

The TCP/IP communication destined for all computers on a network.

IP forwarding

The act of forwarding TCP/IP packets from one network to another. See also routing.

multihomed hosts

The computers that have more than one network interface.

port

The daemons associated with network services listen for network traffic associated with a particular _____. station port IP address allocation number

link local

The portion of an IPv6 address that refers to a unique computer. It is analogous to the host portion of an IPv4 address.

ANDing

The process by which binary bits are compared to calculate the network and host IDs from an IP address and subnet mask.

subnetting

The process in which a single large network is subdivided into several smaller networks to control traffic flow.

PPP over Ethernet (PPPoE)

The protocol used by DSL to send PPP information over an Ethernet connection.

network

Two or more computers joined together via network media and able to exchange information.

The system administrator has shut ethernet interface eth0 down while making some changes to the system. Which of the following commands can they use to bring the network connection back up?

ifup eth0 Correct. The ifup eth0 command can be used to bring ethernet interface eth0 back up.

When connecting to a host via SSH for the first time, the user is prompted to accept the encryption fingerprint for the target computer which is stored in ___________ in the ~/.ssh/ directory.

known_hosts

On a system running NetworkManager, which of the following commands can be used to view or modify connection information?

nmcli Correct. The nmcli command can be used to view or modify connection information on systems running NetworkManager.