Networking Chapter 12

You need to set an IP address for enp2s0 to 192.168.15.2 with a subnet mask of 255.255.255.0. Which commands are correct? (Select two.)

1. ifconfig enp2s0 192.168.15.2 netmask 255.255.255.0 2. ip addr add 192.168.15.2/24 dev enp2s0

As a system administrator, you need to add a static route so that you can reach host 195.156.76.122, 255.255.255.0, and the device eno32 to find the target network. Which of the following commands could you use to accomplish this task? (Select two.)

1. ip route add 195.156.76.0/24 dev eno32 2. route add -net 195.156.76.0 netmask 255.255.255.0 dev eno32

After the acquisition of another company, you need to add another network to the existing routing tables. Which of the following commands could you use to accomplish this task? (Select two.)

1. route add -net 11.12.13.14/24 gw 201.12.3.4 2. ip route add 11.12.13.14/24 via 201.12.3.4

As a system administrator, you are going to add a static route for host 195.157.66.221, 255.255.255.0. Your default gateway is 192.168.5.1, but you want this route to use gateway 192.168.7.1. Which of the following commands could you use to accomplish this task? (Select two.)

1. route add -net 195.157.66.0 netmask 255.255.255.0 gw 192.168.7.1 2. ip route add 195.157.66.0/24 via 192.168.7.1

You check the IP address on a host on the network. The address is 122.16.155.71 with a mask of 255.0.0.0. What is the broadcast address?

122.255.255.255

You are the administrator for a small network of Linux hosts. Your network does not communicate with the internet and does not use DNS. When you add a new host named ENERGY7 to the network, which entry should be added to the /etc/hosts files?

192.168.0.34 ENERGY7 #Reception Area

Out of concern for security, you convinced your IT manager to stop allowing Telnet access to the network. Now remote connections are only made through SSH. Which port must you allow through the firewall for SSH access?

22

You are configuring the IP address for a host. You have been asked to use the address 192.160.99.110/16. Which subnet mask value would you use?

255.255.0.0

Which of the following is a valid IPv6 address?

FEC0::AB:9007

Which of the following tools has commonly replaced ifcfg-type in most modern Linux distributions?

NetworkManager

IPv6 is configured using several methods. In which method is the prefix statically assigned, and the interface ID uses the modified EUI-64 format derived from the MAC address?

Static partial assignment

On the left are recommended steps for completing an effective troubleshooting process. Drag each step to the right in its proper troubleshooting order.

Step 1: Identify the symptoms and potential causes. Step 2: Establish what has changed. Step 3: Create a hypothesis. Step 4: Create an action plan. Step 5: Implement the fix. Step 6: Ensure user satisfaction. Step 7: Document the solution.

What NetworkManager nmcli command can you enter to display a hostname?

nmcli hostname

Alex, a webmaster, recently deployed a new web server. After checking external access to the new web server, he was unable to communicate on port 80. Alex verified that the host-based firewall's configuration had been changed and that the httpd service is running. Which of the following commands will most likely resolve the communication issue?

systemctl restart firewalld

If you are managing a systemd-based Linux system, which of the following commands cannot be used to bring the enp2s0 interface down? (Select two.)

1. /etc/sysconfig/network-scripts/ifcfg-enp2s0 down 2. /etc/init.d/network stop

Which of the following configuration files holds the name of the host?

/etc/hostname

The route add command adds a static route in the routing table and includes several options. Drag a route add option on the left to the correct description on the right.

-host: Specifies a single host on the network. reject: Installs a blocking route. default gw: Creates a route for the default router. -net: Specifies a network address.

Which of the following files provides a list of services and their port assignments used by many firewall applications?

/etc/services

Which of the following are unique features of the firewalld firewall? (Select two.)

1. It uses zones and services instead of chains and rules. 2. You can apply a zone to different network interfaces.

Which of the following should normally be assigned a static IP address on a network?

1. Servers 2. Printers

Which of the following popular Linux firewalls are based on Netfilter? (Select three.)

1. Uncomplicated Firewall (UFW) 2. IPTables 3. firewalld

Which of the following utilities could you use to view the routing table? (Select two.)

1. route 2. ip route show

Which routing component is used to forward packets to remote networks?

Default gateway

You are using a tool on your Linux server to change the IPv4 address for a network card. The tool interface looks like the graphic image below. What tool are you using to change the IP address?

nmtui

As a system administrator, you want to block (reject) any packets from 170.122.0.0, 255.255.0.0. What command will block those packets?

route add 170.122.0.0 netmask 255.255.0.0 reject

You have replaced the default gateway on your network. The gateway had used the IP address 201.12.3.4, and you must remove it from the routing table. What command would you use to accomplish this task?

route del default gw 201.12.3.4

Which of the following IP addresses have a default subnet mask of 255.255.0.0? (Select three.)

1. 168.16.5.1 2. 191.168.2.15 3. 129.0.0.1

Which of the following are Python scripts classified as intrusion prevention software and provide dynamic rule sets to automate the rules IPTables use to filter network traffic? (Select two.)

1. DenyHosts 2. Fail2ban

Which of the following describes an IPv6 address? (Select two.)

1. Eight hexadecimal quartets 2. 128-bit address

Which of the following correctly describes the most common format for expressing IPv6 addresses? (Select two.)

1. Hexadecimal numbers 2. 32 numbers grouped using colons

Which of the following describes link-local IPv6 addresses? (Select three.)

1. Link-local IPv6 addresses must be assigned to any network interface on a Linux system. 2. Link-local IPv6 addresses begin with FE8, FE9, FEA, or FEB. 3. Link-local IPv6 addresses are not routable.

Which of the following are requirements for the default router IP address? (Select two.)

1. Must be configured on each host to allow inter-network communication. 2. Must be on the same subnet as the host computer.

You are troubleshooting a network connection issue for an employee in your company. You are completing step 1 in the troubleshooting process and have already asked the employee to describe the issue and checked for error messages. What else should you do to identify the symptoms and potentials causes of the problem? (Select two.)

1. Recreate the problem. 2. Identify the affected area.

After arriving at work in the morning, you turn on your Linux workstation and attempt to visit an internet news site. After a few minutes, your web browser times out nd tells you that the website is unavailable. Which of the following troubleshooting steps would help you determine the cause of this issue? (Select two.)

1. Use the ping command to ping the FQDN and IP address of the website you are trying to reach. 2. Use the traceroute command to traceroute the FQDN and IP address of the website you are trying to reach.

Which of the following commands can be used to retrieve the IP address and/or the FQDN or hostname information from a DNS server? (Select three.)

1. dig 2. host 3. nslookup

Which of the following features helps provide (by default) confidence in internal networks where only trusted individuals have passwords to the root account?

Privileged ports

IPv6 is configured using several methods. In which method is the entire 128-bit IPv6 address and all other configuration information statically assigned to the host?

Static full assignment

What is the full path and filename of the file you should edit to determine the order in which name resolution is completed?

/etc/nsswitch.conf

Which network service would you use to get the IP address from the Fully Qualified Domain Name (FQDN) hostname?

DNS

In an effort to secure the internal network, you have implemented a host-based firewall and set up ACL rules to accept and reject IP packets for specific ports and services. Some employees are complaining they can no longer access the applications they need. The server is on the internal network connected to an internal router, which is connected to the DMZ, and an external router to the internet. Which of the following is most likely causing problems?

Incorrectly configured ACLs on the firewall.

From the list of IP suite protocols on the left, drag each protocol to the right to match the correct description.

LDAP: Lets you search and update a directory service. ICMP: Works closely with IP to provide error and control information. SSL: Uses RSA to secure messages being transmitted on the internet. SNMP: Designed for managing complex networks. SMTP: Used to route electronic mail through the internetwork.

In which of the following IPv6 configuration methods does the RA message contain configuration information to obtain the interface ID, subnet prefix, default gateway, and other configuration information from a DHCPv6 server?

Stateful autoconfiguration

IPv6 is configured using several methods. In which method do the clients automatically generate the interface ID and learn the subnet prefix and default gateway through Neighbor Discovery Protocol (NDP)?

Stateless autoconfiguration

You are an application developer. You are writing a program to exchange video files through a TCP/IP network. You need to select a transport protocol that will guarantee delivery. Which TCP/IP protocol would you implement to provide this capability?

TCP

Which of the following provides a user-friendly framework for managing the Netfilter firewall?

Uncomplicated Firewall

IPv6 uses 128-bit addresses. The address contains two 64-bit components.

What is the first 64-bit component called?: The prefix What is the last 64-bit component called?: The interface ID

When configuring bonding on two network interfaces, the technician wants to configure one interface to take over if the other interface fails. Which of the following bonding modes should be used to provide a hot standby?

active-backup, or mode 1

What would you enter at the command prompt to find the IP address for the xyzcomp.com domain?

host xyzcomp.com

You need to temporarily change the IP address of the network interface (enp2s0) to 192.168.1.50. The network interface's IP address is currently set to 10.0.1.50. Which of the following commands would achieve the desired result?

ifconfig enp2s0 192.168.1.50

The enp2s0 interface is currently down. What can you enter at the command-line to start the enp2s0 interface?

ifup enp2s0

The enp2s0 network interface has already been assigned the IP configuration 172.16.1.123/16. What command would you use to temporarily configure a second IP address of 192.168.0.123/24 for this network interface?

ip addr add 192.168.0.123/24 dev enp2s0

A technician is configuring a server with four network interface cards to use a round-robin scheduling algorithm for bonding. This algorithm transmits packets on the first available network interface. Which of the following is provided by this configuration?

load balancing

Which of the following commands combines the functionality of the traceroute and ping commands in a single network diagnostic tool?

mtr

You are troubleshooting a connectivity problem on a Linux server. You are able to connect to another system on the local network, but you are not able to connect to a server on a remote network. You suspect that the default gateway information for the system may be configured incorrectly. Which of the following commands would you use to view the default gateway information on the Linux server?

netstat -r

NetworkManager provides a graphical user interface used on many Linux desktops. It also provides a semi-graphical interface that you can launch from a shell prompt that uses hotkeys, arrow keys, and Enter to manage network settings. In addition, there is also a command you can use to perform the same tasks. What is the NetworkManager command you can use to manage network settings?

nmcli

You want to use the nmcli command to display information about your Linux servers from NetworkManager. You would like to view the information in an easily-readable format. Which of the following commands would meet your requirement?

nmcli -p

Which of the following commands can you enter to verify that NetworkManager is running? (Select the correct answer from the drop-down list.)

nmcli -t -f RUNNING general

What NetworkManager nmcli command can you enter to list all the available network connections? (Select the correct answer from the drop-down list.)

nmcli con show

What NetworkManager nmcli command can you use to display the state of the current network connections?

nmcli general

Which of the following NetworkManager nmcli commands can you use to update the hostname?

nmcli general hostname <newhostname>

NetworkManager provides a graphical user interface used on many Linux desktops. However, it also provides a text user interface that you can launch from a shell prompt that uses hotkeys, arrow keys, and Enter to manage network settings. What is the command you can use to launch this utility?

nmtui

Which of the following files contains information that enables a Linux system to resolve IP addresses to FQDN/hostnames? (Select two.)

1. /etc/hosts 2. /etc/resolv.conf

Maria, a system administrator, wants to set up IP forwarding on a server for both IPv4 and IPv6. Which of the following files should be modified to enable IP forwarding? (Select two.)

1. /proc/sys/net/ipv6/ip_forward 2. /proc/sys/net/ipv4/ip_forward

You are configuring a network firewall to allow SMTP outbound email traffic and POP3 inbound email traffic. Which of the following TCP/IP ports should you open on the firewall? (Select two.)

1. 110 2. 25

You have a computer that is connected to the internet through a NAT router. You want to use a private addressing scheme for your computer. Which of the following IP addresses could you assign to the computer? (Select three.)

1. 192.168.12.253 2. 172.18.188.67 3. 10.0.12.15

To transfer files to your company's internal network from home, you use FTP. The administrator has recently implemented a firewall at the network perimeter and disabled as many ports as possible. Now you can no longer make the FTP connection. You suspect the firewall is causing the issue. Which ports need to remain open so you can still transfer the files using the FTP protocol? (Select two.)

1. 20 2. 21

Which of the following are not valid IP addresses? (Select three.)

1. 45.22.156.256 2. 257.0.122.55 3. 145.8.260.7

Which of the following are valid IPv6 addresses? (Select two.)

1. 6384:1319:7700:7631:446A:5511:8940:2552 2. 141:0:0:0:15:0:0:1

A routing table typically contains which of the following information? (Select two.)

1. A timeout value that identifies when the route expires. 2. The interface or next hop router used to reach the destination network.

Which of the following are tasks you can perform with the NetworkManager Text User Interface (nmtui)? (Select two.)

1. Configure IPv4 and IPv6 addresses 2. Change the hostname configuration

Which of the following are IP packet characteristics that ACL rules look at to determine how to filter a packet? (Select three.)

1. Ports 2. Protocols 3. Source address

You are asked to troubleshoot a problem on an employee's computer. When the employee types the name of any website they receive a message stating, "The page cannot be displayed." You determine that nothing has changed on the computer. What is the MOST likely problem?

The DNS server is down or not reachable.

You have a TCP/IP network with 50 hosts. There have been inconsistent communication problems between hosts. You run a protocol analyzer and discover that two hosts are assigned the same IP address. Which protocol can you implement on your network to help prevent problems such as this?

DHCP

What should you do to enable DHCP across subnets?

Enable BootP requests through the router.

You are the system administrator of a test lab that uses the Linux operating system. For security reasons, your lab is not connected to the corporate network, and you are not able to resolve hostnames via the corporate DNS server. You want to be able to connect to the lab computers using hostnames, but you do not have the resources to bring up your own DNS server. Which of the following solutions would satisfy your requirements?

Enter the IP addresses and hostnames for all of the lab computers in the /etc/hosts file on each of the machines in the lab.

Your ISP has changed the IP addresses of their DNS servers. What would you need to do on your Linux system to be still able to continue resolving host and fully qualified domain names if you use statically assigned IP address information?

Enter the IP addresses of the new DNS servers into the /etc/resolv.conf file.

You are attempting to ping another computer on the internet by its IP address, but you are not getting a response. You do get a response when you ping a host on your own network. Which of the following options would help you better determine where the problem is?

Run traceroute on the IP address of the computer on the internet.

While working on a storage device access problem on your company network, you have already created a hypothesis and are ready to create an action plan. Which of the following might be part of that action plan?

Taking the storage device offline for a period of time.

You open the /etc/nsswitch.conf file and see the following line: hosts: files dns What is the result of this configuration?

The /etc/hosts file takes precedence over the information obtained from a DNS server when resolving domain names.

As the IT System Administrator, you recently set up a new DHCP server, DHCP_03. You want to test connectivity on port 53 from other servers on the network. Which of the following commands will accomplish that task?

nc -zv DHCP_03 53