Pt.3 Ch.16 Networking Flashcards

1
Q

What does a ping command send?

A

a special network packet called an ICMP ECHO_Request to a specified host

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is often times done in regard to ping for security reasons?

A

The network devices are configured to ignore these packets. It partially obscures a host from a potential attacker. It is also common for firewalls to be configured to block ICMP traffic.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What would pinging linuxcommand.org on the command line look like?

A

ping linuxcommand.org

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How do you interrupt a ping packet?

A

Ctrl-c

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What does the traceroute program do?

A

it lists all the “hops” network traffic takes to get from the local system to a specified host.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What information is provided by traceroute?

A

hostnames, IP addresses, performance data, round-trip time from the local system to the router (x3).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How do you get around being withheld information in traceroute?

A

traceroute -T site.com

traceroute -I site.com

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What system allows us to examine a system’s network interfaces and routing table?

A

ip

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the loopback interface?

A

lo. A virtual interface that the system uses to “talk to itself”. Found via ip a

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is eth0

A

The Ethernet interface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

When performing casual network diagnostics, what are the important things to look for?

A
  1. the presence of the word UP in the first line for each interface (indicating that the network interface is enabled) 2. the presence of a valid IP address in the inet field on the third line 3. For system usings DHCP, a valid IP address in this field will verify that the DHCP is working.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does DHCP stand for

A

Dynamic Host Configuration Protocol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is used to examine various network settings and statistics?

A

netstat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How do we examine the network interfaces in our system?

A

netstat -ie

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How do we display the kernel’s network routing table?

A

netstat -r

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

IP addresses that end in zero refer to what?

A

Networks rather than individual hosts

17
Q

What does FTP stand for?

A

File Transfer Protocol

18
Q

Why is the original form of ftp not secure?

A

it sends account names and passwords in cleartext.

19
Q

What file transfer protocol does raspbian have?

A

sftp

20
Q

What is wget good for?

A

Downloading content from both web and ftp sites, as well as single files, multiple files, and even entire sites.

21
Q

How would you download the first page of linuxcommand.org?

A

wget linuxcommand.org

22
Q

What protocol is used for secure communication with Remote Hosts?

A

Secure Shell (SSH)

23
Q

What two basic problems of secure communication with a remote host does ssh solve?

A
  1. It authenticates that the remote host is who it says it is (thus preventing so-called man-in-the-middle attacks). 2. It encrypts all of the communications between the local and remote hosts.
24
Q

What are the two parts an SSH consists of?

A
  1. an SSH server 2. an SSH client
25
Q

What does an SSH server do and where is it located?

A

it runs on the remote host and listens for incoming connections (by default on port 22).

26
Q

What does an SSH client do and where does it reside?

A

It’s used on the local system to communicate with the remote server.

27
Q

How does SSH for Ubuntu differ?

A

It only supplies the SSH client.

28
Q

What do most linux distributions come with for SSH?

A

OpenSSH from the OpenBSD project

29
Q

What has to happen to enable a system to receive remote connections?

A

it must have the OpenSSH-server package installed, configured and running, and it must allow incoming network connections on TCP port 22.