What command can you use to verify that a host computer can connect to the TCP/IP network and network resources?

What command can you use to verify that a host computer can connect to the TCP/IP network and network resources?

• ping
• tracert
• netstat
• nslookup 

EXPLANATION

Testing Connections to Remote Servers

If you cannot connect to a remote server, there are two common tools that you can use. Use the PING command to verify that a host computer can connect to the TCP/IP network and network resources. Use the TRACERT command to examine the route taken to a destination.

To Test Connections by Using PING
You can use the PING command as a troubleshooting tool to sequentially test connectivity to various network resources. To "ping" a network host directly:

1. Click Start, click Run, type cmd in the Open box, and then press ENTER.
2. Type one of the following lines, and then press ENTER, where IPAddressOfRemoteNetworkHost is the IP address of the computer that you want to connect to, and HostName is the name of the computer that you want to connect to:

• ping IPAddressOfRemoteNetworkHostFor example, ping 192.168.104.
• ping HostNameFor example, ping quiz.techlanda.com.

3.In the command prompt window, look for a reply that may look similar to the following:

Reply from 192.168.1.104: bytes=32 time=40ms TTL=61
Reply from 192.168.1.104: bytes=32 time=40ms TTL=61
Reply from 192.168.1.104: bytes=32 time=40ms TTL=61
Reply from 192.168.1.104: bytes=32 time=40ms TTL=61
If you receive a similar response, the server is available on the network. If you cannot contact the resource, you can troubleshoot the connection by using the PING command to test connectivity to various network resources:

a. Ping the loopback address to verify that TCP/IP is installed and working correctly on the local computer. To do so, type ping 127.0.0.1.
b. Ping the IP address of the local computer to verify that it was added to the network correctly.
c. Ping the IP address of the default gateway to verify that the gateway is functional and it is possible to connect to a local host on the local network. You can obtain the IP address of the local default gateway by using the IPCONFIG command.
d. Ping the IP address of another remote host to verify that you can communicate through a router.NOTE: To see additional options of the Ping.exe tool, type ping /? at the command prompt.
To Test Connections by Using Tracert.exe
loadTOCNode(3, 'summary');
Tracert.exe is a route-tracing utility that you can use to determine the network path to a destination. The TRACERT command shows the series of IP routers that are used to deliver packets from your computer to the destination and shows how long it takes for each hop. If packets cannot reach the destination, the TRACERT command returns the name of the last router that successfully forwarded the packets. To determine the path that a packet takes on the network and where that path may be ending:
1. Click Start, click Run, type cmd in the Open box, and then press ENTER.
2. At the command prompt, type tracert IPAddressOfRemoteNetworkHost, and then press ENTER, where IPAddressOfRemoteNetworkHost is the IP address of the remote network host.
3. Examine the results that appear in the window to determine the length of time that the packet took to reach each network segment and the point at which the connection may stop working.
NOTE: To see additional options of the Tracert.exe tool, type tracert /? at the command prompt.

 

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Which of the following folder names can NOT be used with Windows?

Which of the following folder names can NOT be used with Windows?

• MAK
• CON
• CAN
• SUB 

EXPLANATION

You can’t create folders in Windows OS having CON, PRN, NUL, etc. as the name. This is because these folder names are reserved for use in specific system tasks. You can use the command prompt, or blank space code to create folders with reserved names in Windows. In Microsoft Windows operating system, you can’t create folders that have their name from one of these words:

CON, PRN, AUX, NUL, COM1, COM2, COM3, COM4, COM5, COM6, COM7, COM8, COM9, LPT1, LPT2, LPT3, LPT4, LPT5, LPT6, LPT7, LPT8, and LPT9.
Also, you can’t add file extensions with these names. For instance, you can’t create NUL.mp3 folder.
The reason is these keywords are reserved for some tasks to be performed by the OS. It uses these words to create folders from time to time and store data in them for tasks related to printing and other functions. We creating a folder with the same name would confuse the system.
The history of these reserved Windows folder names dates back to the time when Microsoft was known for its DOS operating system. Since then, no change has been made to these names. You might’ve read a similar story on Fossbytes, why the first drive letter is C?

You can still create CON, PRN folders

Although it’s hard to name a Windows folder as CON or PRN directly, a workaround is possible. Before proceeding further, I would like to tell you that Windows also doesn’t allow a folder name only comprising of a blank space.
You can create a folder without a name or one of the reserved names using a key combination.

1. Create a new folder, or click the rename option for an existing folder.
2. Delete all the text written in the name field.
3. Press and hold the ALT key and type 255 on the “Numpad”. As you enter the key combination, you won’t see anything typed in the name field.
4. After this, type the desired name and press Enter. Or don’t enter any name to create a Windows folder without a name.

The key combination ALT+255 is a code used to introduce a blank space in Windows. You are just adding an extra invisible character to create a folder name CON or PRN.

Create CON, PRN folders using the command line?

For most Windows users, command prompt or CMD is probably the last mile solution for a problem. But it’s effective. You can use the command prompt in Windows to create folders with reserved names.

1. To open CMD, right on the Start button and click Command Prompt.
2. Now type the following command to create a folder name CON on the desktop (Copy the path to your desktop):
   md C:\Users\techlanda\Desktop\con\
3. Press Enter. You can create other reserved Windows folder using CMD. Also, you can change the location where want to create the folder.
4. Delete the CON folder:
   rd C:\Users\techlanda\Desktop\con\

Although we can create the folder successfully, it is still inaccessible. Also, it can only be deleted using the command line. I would recommend not to use the command-line method.

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To be part of a VTP domain, what must all switches have configured?

To be part of a VTP domain, what must all switches have configured?

• IP address in the management VLAN
• VTP MD5 authentication
• Same VTP Version
• Switchports in host mode for all connecting ports

EXPLANATION

VTP Configuration Guidelines

This section provides some guidelines for the configuration of VTP in the network.

• All switches have the same the VTP domain name, unless the network design insists for different VTP domains.
  Note: Trunk negotiation does not work across VTP domains. Refer to the Data Traffic Blocked between VTP Domains section of Troubleshooting VLAN Trunk Protocol (VTP) for more information.
  
• All switches in a VTP domain must run the same VTP version.
  
• All switches in a VTP domain has the same VTP password, if there is any.
  
• All VTP Server switch(es) should have the same configuration revision number and it should also be the highest in the domain.
  
• When you move a VTP mode of a switch from Transparent to Server, VLANs configured on the VTP Transparent switch should exist on the Server switch.
  

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By default, what command-line text editor does Raspberry Pi use?

By default, what command-line text editor does Raspberry Pi use?

• vi
• nano
• vim
• editit 

EXPLANATION

Text editors

On Linux, you have a choice of text editors. Some are easy-to-use but have limited functionality; others require training to use and take a long time to master, but offer incredible functionality.

Desktop graphical editors

Leafpad

On Raspbian, you'll find an editor called Leafpad. This is a simple editor which opens in a window like a normal application. It allows use of the mouse and keyboard, and has tabs and syntax highlighting.
You can use keyboard shortcuts, such as Ctrl + S to save a file and Ctrl + X to exit.

Thonny

Thonny is a Python REPL and IDE, so you can write and edit Python code in a window and run it from there.
Thonny has independent windows and syntax highlighting, and uses Python 3

GVim

See Vim below.

Geany

A fast and lightweight IDE, supporting many different file types, including C/C++ and Python. Installed by default on Raspbian.

Command-line editors

Nano

GNU Nano is at the easy-to-use end of command-line editors. It's installed by default, so use nano somefile.txt to edit a file, and keyboard shortcuts like Ctrl + O to save and Ctrl + X to exit.

Vi

Vi is a very old (c. 1976) command-line editor, which is available on most UNIX systems and is pre-installed on Raspbian. It's succeeded by Vim (Vi Improved), which requires installation.
Unlike most editors, Vi and Vim have a number of different modes. When you open Vi with vi somefile.txt, you start in command mode which doesn't directly permit text entry. Press i to switch to insert mode in order to edit the file, and type away. To save the file you must return to command mode, so press the Escape key and enter :w (followed by Enter), which is the command to write the file to disk.
To search for the word 'raspberry' in a file, make sure you're in command mode (press Escape), then type /raspberry followed by n and N to flick forwards/backwards through the results.
To save and exit, enter the command :wq. To exit without saving, enter the command :q!.
Depending on your keyboard configuration, you may find your cursor keys don't work. In this case, you can use the H-J-K-L keys (which move left, down, up, and right respectively) to navigate the file in command mode.

Vim

Vim is an extension of Vi and works in much the same way, with a number of improvements. Only Vi is installed by default so to get the full features of Vim, install it with APT:

sudo apt-get install vim

You can edit a file in Vim with vim somefile.txt. Vim also has a graphical version which opens in a window and allows interaction with the mouse. This version is installable separately:

sudo apt-get install vim-gnome

To use the graphical version of Vim, use gvim somefile.txt. You can save configuration in a .vimrc file in your user's home directory. To learn more about editing in Vi and Vim, you can run vimtutor and follow the tutorial.

Emacs

Emacs is a GNU command-line text editor; it's powerful, extensible, and customisable. You can install it with APT:

sudo apt-get install emacs

You can use keyboard combination commands, such as Ctrl + X Ctrl + S to save and Ctrl + X Ctrl + C to close.

 

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Which of the following do you need to take care of when you adopt a cloud solution?

Which of the following do you need to take care of when you adopt a cloud solution?

• Network router configuring
• Writing script to automate VM deployment
• Security auditing
• Performance monitoring 

EXPLANATION

IT security audits determine whether an information system and its maintainers meet both the legal expectations of customer data protection and the company’s standards of achieving financial success against various security threats. These goals are still relevant in the emerging cloud computing model of business, but they require customization.

Cloud computing, as defined by the National Institute of Standards and Technology (NIST), is “a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction.” ¹ In essence, cloud computing could be described as the use of computing resources—both hardware and soft ware—provided over a network, requiring minimal interaction between users and providers.

Three service models are commonly implemented in the cloud: soft ware as a service (SaaS), platform as a service (PaaS), and infrastructure as a service (IaaS). In each of these service types, security is a signifi cant challenge. Security audits provide a clear and recognizable trail of resource access for various organizations.

Traditional IT audits typically fall into two main categories: internal and external. Internal audits refer to work done by an organization’s own employees, concern very specific organizational processes, and focus primarily on optimization and risk management. External audits give an outside perspective on an organization’s ability to meet the requirements of various laws and regulations. Organizations have used traditional IT audits to evaluate issues such as availability to authorized users and integrity and confidentiality in data storage and transmission.
But what happens when an organization’s IT resources are moved to the cloud? Because cloud computing allows for multiple users across a large domain, it exposes novel security issues such as cloud-specifi c confi dentiality concerns. These threats pose new challenges for security auditing, but cloud advocates are responding to them. For instance, groups such as Cloud Security Alliance (CSA) are urging standardization of cloud confi dentiality, integrity, and availability auditing.

 

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