IT Questions and Answers :)

Monday, April 30, 2018

Computers need to maintain certain settings (for example, date, time, some hardware settings, etc.) even when they are completely powered off. Such settings are used at start-up (among other uses). Where are these settings stored and maintained?

Computers need to maintain certain settings (for example, date, time, some hardware settings, etc.) even when they are completely powered off. Such settings are used at start-up (among other uses). Where are these settings stored and maintained?

  • In the BIOS
  • In Zone 0 of the hard drive
  • In the CMOS
  • In the Operating System 

 
Computers need to maintain certain settings (for example, date, time, some hardware settings, etc.) even when they are completely powered off. Such settings are used at start-up (among other uses). Where are these settings stored and maintained?

EXPLANATION

CMOS, which stands for "Complementary Metal-Oxide Semiconductor", is a battery-powered semiconductor chip that stores information such as date, time and certain hardware settings. A tiny battery, similar to a watch battery, is what allows the CMOS to maintain information while the machine is powered off. As they are typically designed to last about ten years, and since most computers get scrapped before then, this is why you probably haven't had to replace many CMOS batteries.

While the BIOS uses data from the CMOS, these are two separate things. See the following for more information on the difference between the two and how they work together: http://www.computerhope.com/issues/ch001360.htm

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Saturday, April 28, 2018

How many kibibytes (KiB) are in 1 tebibyte (TiB)?

How many kibibytes (KiB) are in 1 tebibyte (TiB)?

  • 1,073,741,824 KiB
  • 1,048,576 KiB
  • 10,240,000,000 KiB
  • 1,000,000 KiB 

 
How many kibibytes (KiB) are in 1 tebibyte (TiB)?

EXPLANATION

The interpretation of the older term "kilobyte" to denote 1024 bytes, conflicting with the SI definition of the prefix kilo (1000), is still common, mostly in informal computer science contexts
1 kibibyte = 1,024 bytes
1 mebibyte = 1,024 kibibytes
1 gibibyte = 1,024 mebibytes = 1,048,576 kibibytes
1 tebibyte = 1,024 gibibytes = 1,048,576 mebibytes = 1,073,741,824 kibibytes
https://en.wikipedia.org/wiki/Kibibyte

SOURCE

https://en.wikipedia.org/wiki/Kibibyte
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What TCP port is SFTP or Secure File Transfer Protocol commonly used on?

What TCP port is SFTP or Secure File Transfer Protocol commonly used on?

  • 7777
  • 69
  • 22
  • 21 

 
What TCP port is SFTP or Secure File Transfer Protocol commonly used on?

EXPLANATION

Secure File Transfer Protocol is commonly placed on 22 as it is also known as File Transfer Protocol on SSH. Not to be confused with File Transfer Protocol over TLS/SSL or FTPS, as there are no answers for ports 989 or 990.
 For more information, see:
https://support.apple.com/en-us/HT202944
https://www.infobyip.com/tcpportchecker.php
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What are the tones called when you press a key on your telephone?

What are the tones called when you press a key on your telephone?

  • Multiple Frequency Tone Signal
  • Dual Signal Tone Frequency
  • Dual Tone Multiple Frequency (MF4)
  • Single Tone Frequency 
What are the tones called when you press a key on your telephone?

EXPLANATION

DTMF (dual tone multi-frequency) is the beeping signal to the phone company that you generate when you press an ordinary telephone's touch keys.

https://en.wikipedia.org/wiki/Dual-tone_multi-frequency_signaling

SOURCE


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What is DCL used for in SQL?


What is DCL used for in SQL?

  • Monitor database transactions
  • Solving deadlock situations
  • Control access to data stored in a database
  • Control database size and archiving schedule 

 

EXPLANATION

A data control language (DCL) is a syntax similar to a computer programming language used to control access to data stored in a database (Authorization). In particular, it is a component of Structured Query Language (SQL).
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Monday, April 23, 2018

Amazon DNS service is called?

Amazon DNS service is called?

  • EC2
  • S3 Bucket
  • SES
  • Route 53 
 
Amazon DNS service is called?

EXPLANATION

Amazon Route 53 is a highly available and scalable cloud Domain Name System (DNS) web service. It is designed to give developers and businesses an extremely reliable and cost effective way to route end users to Internet applications by translating names like www.example.com into the numeric IP addresses. 

SOURCE

https://aws.amazon.com/route53/
 
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Friday, April 20, 2018

In PowerShell, which of the following is a feature that you use to assign a set of commands (optionally with input parameters) to execute by a single name?

In PowerShell, which of the following is a feature that you use to assign a set of commands (optionally with input parameters) to execute by a single name?

  • subroutine
  • procedure
  • function
  • method 

 
In PowerShell, which of the following is a feature that you use to assign a set of commands (optionally with input parameters) to execute by a single name?

EXPLANATION


In PowerShell, functions can act like miniature scripts within scripts which are executed by name, and they can be everything from a few commands, to full blown cmdlets written entirely in PowerShell (called Advanced Functions).
about_Functions on MSDN: https://msdn.microsoft.com/en-us/powershell/reference/4.0/microsoft.powershell.core/about/about_func...
about_Functions_Advanced on MSDN: https://msdn.microsoft.com/en-us/powershell/reference/4.0/microsoft.powershell.core/about/
Methods exist in PowerShell as well, as members of .NET objects: https://msdn.microsoft.com/en-us/powershell/reference/4.0/microsoft.powershell.core/about/about_meth...
Note: you can also access the above three directly in PowerShell with the commands:
Get-Help about_Functions
Get-Help about_Functions_Advanced
Get-Help about_Methods
Going beyond PowerShell, this is mostly a naming convention: the differences between the four names seem to vary from language to language.  While there are general technical definitions for each of the terms (for instance, "functions return a value; procedures do not"), these are not used universally among languages and programmers; as such, it's generally best to follow the naming convention common to the specific language.For more reading on the terms: http://softwareengineering.stackexchange.com/questions/20909/method-vs-function-vs-procedure

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Thursday, April 19, 2018

In Windows, What does the "ping -a" command allow you to find out about an IP address?

In Windows, What does the "ping -a" command allow you to find out about an IP address?

  • Router address of the host
  • IP address of the host
  • Resolve the host name
  • Default gateway of the host 

 
In Windows, What does the "ping -a" command allow you to find out about an IP address?

EXPLANATION

In many cases, the "ping -a" command will return the host name if you know the IP address.
This is a good first step when attempting to identify the host.

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Wednesday, April 18, 2018

A hypervisor that runs directly on top of hardware (as opposed to on an OS) is known as:

A hypervisor that runs directly on top of hardware (as opposed to on an OS) is known as:

  • Side saddle
  • Hosted
  • Bare metal
  • Type 2 

 
A hypervisor that runs directly on top of hardware (as opposed to on an OS) is known as:

EXPLANATION

A bare-metal (also known as native or type-1) hypervisor runs directly on the host's hardware to control the hardware and to manage guest operating systems. For this reason, they are sometimes called bare-metal hypervisors.
A guest operating system runs as a process on the host.
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Tuesday, April 17, 2018

Which benefit of being joined to a domain is not natively shared by Apple Macintosh computers?

Which benefit of being joined to a domain is not natively shared by Apple Macintosh computers?

  • Group Policy
  • Password Policy Enforcement
  • Single Sign-On
  • Windows Home Folders 

 
Which benefit of being joined to a domain is not natively shared by Apple Macintosh computers?

EXPLANATION


A domain-joined Mac workstation allows users to enjoy the following privileges:
  • Kerberos authentication and delegation, including Single Sign-On to local, AD, and Open Directory resources
  • AD password policy enforcement
  • Support for AD user and group accounts
  • Windows home folders
Of course, Mac computers do not have a Windows Registry and so therefore cannot be managed natively by Group Policy (the password policy issue previously mentioned is a notable exception).

SOURCE

https://4sysops.com/archives/how-to-join-a-mac-os-x-computer-to-active-directory/
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Friday, April 13, 2018

In Linux and Unix systems, what directory is most likely to contain system configuration data?

In Linux and Unix systems, what directory is most likely to contain system configuration data?

  • /boot/
  • ~/.config
  • /usr/share/doc
  • /etc/ 
 
In Linux and Unix systems, what directory is most likely to contain system configuration data?

EXPLANATION

As a rule, system configuration data should be kept in /etc/ http://tldp.org/LDP/Linux-Filesystem-Hierarchy/Linux-Filesystem-Hierarchy.pdf This can be quite useful knowledge when figuring out backup and recovery plans!
 
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Thursday, April 12, 2018

You setup your server to accept PPTP VPN client connections. You accurately port forward TCP 1723 on the firewall to the server, but clients still cannot connect. Of the below options, what would be the most likely reason?

You setup your server to accept PPTP VPN client connections. You accurately port forward TCP 1723 on the firewall to the server, but clients still cannot connect. Of the below options, what would be the most likely reason?

  • GRE not enabled or blocked on the firewall.
  • Port forward of UDP 1723 missing.
  • No static routes configured on the firewall.
  • Port forward of UDP 500 missing.
You setup your server to accept PPTP VPN client connections. You accurately port forward TCP 1723 on the firewall to the server, but clients still cannot connect. Of the below options, what would be the most likely reason?

EXPLANATION

GRE is an encapsulation protocol required by some PPTP VPN connections, notably Microsoft's implementation. Some cheaper and consumer level firewall/routers do not support or have an option for GRE, or if it does it might be disabled or blocked.
UDP 500 is specific to IPSEC.
Along with the citation, also see...
http://whp-aus1.cold.extweb.hp.com/pub/networking/software/ProCurve-SR-dl-GRE-Config-Guide.pdfhttp://www.cisco.com/c/en/us/support/docs/ip/generic-routing-encapsulation-gre/118361-technote-gre-0....
https://en.wikipedia.org/wiki/Generic_Routing_Encapsulation

SOURCE

https://blogs.technet.microsoft.com/rrasblog/2009/08/12/troubleshooting-common-vpn-related-errors/
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Convert 101101 from binary to decimal!

Convert 101101 from binary to decimal!

  • 44
  • 61
  • 45
  • 41 

Convert 101101 from binary to decimal!

EXPLANATION

Each 1 represents a power of 2, so this is equivalent to 2^5 + 2^3 + 2^2 + 2^0, or 32 + 8 + 4 + 1 = 45.

1 x 1 = 1
0 x 2 = 0
1 x 4 = 4
1 x 8 = 8
0 x 16 = 0
1 x 32 = 32

1 + 4 + 8 + 32 = 45
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Wednesday, April 11, 2018

What's a stealthy and continuous computer hacking process often targeted at a specific entity?

What's a stealthy and continuous computer hacking process often targeted at a specific entity?

  • Shadow ninja attack
  • Advanced persistent threat
  • Advanced malware attack
  • Silent and deadly attack 

 
What's a stealthy and continuous computer hacking process often targeted at a specific entity?

EXPLANATION

An advanced persistent threat (APT) uses multiple phases to break into a network, avoid detection, and harvest valuable information over the long term. The intention of an APT attack is to steal data rather than to cause damage to the network or organization. APTs require a high degree of covertness over an extended period of time.
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Tuesday, April 10, 2018

Which of these cloud distribution models delivers a licensed application to customers over the Internet as an on-demand service?

Which of these cloud distribution models delivers a licensed application to customers over the Internet as an on-demand service?

  • Platform as a service
  • Infrastructure as a service
  • Security as a service
  • Software as a service 

Which of these cloud distribution models delivers a licensed application to customers over the Internet as an on-demand service?


EXPLANATION

Software as a service, or "software on demand," is a software licensing and delivery model where a vendor hosts an application and allows you to download it for a set period of time.
This can be handy if your business wants access to a particular application without the upfront costs of purchasing a full license or dealing with maintenance.
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Monday, April 9, 2018

In which OSI layer does the UDP protocol operate?

In which OSI layer does the UDP protocol operate?

  • Data link
  • Network
  • Session
  • Transport
 
In which OSI layer does the UDP protocol operate?

EXPLANATION




Both TCP and UDP are transport protocols, belonging to the transport layer of the OSI model. Both TCP and UDP run on top of IP, which operates at the network layer.
 
 
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In PowerShell, what cmdlet corresponds to the "FL" alias?

In PowerShell, what cmdlet corresponds to the "FL" alias?

  • Format-Line
  • Format-List
  • For-Loop
  • Folder-Limit 

 
In PowerShell, what cmdlet corresponds to the "FL" alias?

EXPLANATION

Format-List is the long form of the "FL" command. This command is used to change the layout of list items when they are output to the console.
For-Loop, Folder-Limit, and Format-Line are not PowerShell commands.

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Thursday, April 5, 2018

Which of the following would be your first EIGRPv6 command in a new cisco router?

Which of the following would be your first EIGRPv6 command in a new cisco router?

  • interface config: ipv6 eigrp 1
  • global config: ipv6 unicast-routing
  • global config: ipv6 router eigrp 1
  • interface config: ipv6 unicast 

 
Which of the following would be your first EIGRPv6 command in a new cisco router?

EXPLANATION

EIGRPv6 involves the following configuration steps:
- Enable IPv6 routing using the ipv6 unicast-routing command.
- Create an EIGRPv6 process using ipv6 router eigrp asn command.
- Assign an EIGRPv6 router ID using the eigrp router-id router-id command in router configuration mode.
- Enable EIGRPv6 on interfaces using the ipv6 eigrp asn command in interface configuration mode

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In SAP how does a end-user make modifications to their account, for instance change a Printer?

In SAP how does a end-user make modifications to their account, for instance change a Printer?

  • Extras Menu->Settings
  • SU3 or System Menu -> User Profile -> Own Data
  • SAPUSER02
  • US3 or System Menu->Services->Output Control 

 In SAP how does a end-user make modifications to their account, for instance change a Printer?

EXPLANATION

In SAP an individual user account can make certain changes to their account.  Usually this is the Output device, Date Format and Decimal notation.  Administrators can lock out changes to specific fields.
SU3 Maintain Users Own Data

SOURCE


http://www.sapbasiskapil.com/2013/07/how-to-setup-default-printer-in-sap-su3.html
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What does the ALTER TABLE clause do ?

What does the ALTER TABLE clause do ?

  • The SQL ALTER TABLE clause modifies a table definition by altering, adding, or deleting table column
  • The SQL ALTER TABLE clause is used to insert data into database table
  • The SQL ALTER TABLE deletes data from database table
  • The SQL ALTER TABLE clause is used to delete a database table 

 
What does the ALTER TABLE clause do ?

EXPLANATION

Answer is A. SQL ALTER TABLE:  Modifies a table definition by altering, adding, or dropping columns and constraints, reassigning and rebuilding partitions, or disabling or enabling constraints and triggers.


SOURCE

https://docs.microsoft.com/en-us/sql/t-sql/statements/alter-table-transact-sql
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The software layer that abstracts physical resources from the VMs or operating systems running on top is the:

The software layer that abstracts physical resources from the VMs or operating systems running on top is the:

  • Compiler
  • Browser
  • Hypervisor
  • VMBus 

 
The software layer that abstracts physical resources from the VMs or operating systems running on top is the:

EXPLANATION

A hypervisor is computer software that creates and runs virtual machines. A hypervisor also divides the physical resources of a server and allocates them to all of the VMs that it manages.
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What does a bcache in Linux do?

What does a bcache in Linux do?

  • "B" stands for binary coding, the bcache is an prior chaching method.
  • Bcache is a advanced technology to encrypt your cache as an addition to full disc encryption.
  • Bcache has nothing to do with Linux.
  • Allows faster storage devices to act as caching devices for slower storage devices. 


EXPLANATION

Bcache allows one to use an SSD as a read/write cache (in writeback mode) or read cache (writethrough or writearound) for another blockdevice (generally a rotating HDD or array). For an intro to bcache itself, see the bcache homepage.

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Wednesday, April 4, 2018

What does an HTTP error 403 mean?

What does an HTTP error 403 mean?

  • That webpage no longer exists
  • The website cannot display the page
  • Access to the webpage is forbidden
  • The webpage cannot be found 

 
What does an HTTP error 403 mean?

EXPLANATION




HTTP error 403 means that the website declined to show this webpage. The browser is able to reach the server but the server refuses to take any further action. This can happen for a variety of reasons; here are some of the most common:
  • The website's administrator has to give you permission to view the page or the web server doesn't accept public web page requests. If this is a website that you should have access to, contact the website administrator.The web page you're trying to view is generated by a program, such as a shopping cart or search engine, and the folder on the server the program is contained in isn't correctly configured by the website administrator.You've typed a basic web address (for example, www.example.com), but the website doesn't have a default web page (such as index.htm or default.html). Additionally, the website doesn't allow directory listing, which allows you to view files in a web folder.
  • The website's administrator has to give you permission to view the page or the web server doesn't accept public web page requests. If this is a website that you should have access to, contact the website administrator.
  • The web page you're trying to view is generated by a program, such as a shopping cart or search engine, and the folder on the server the program is contained in isn't correctly configured by the website administrator.

  • You've typed a basic web address (for example, www.example.com), but the website doesn't have a default web page (such as index.htm or default.html). Additionally, the website doesn't allow directory listing, which allows you to view files in a web folder.
HTTP error code 404 means that the webpage cannot be found. HTTP error code 410 means that web page no longer exists, and HTTP error 405 occurs when a website cannot display the page.

SOURCE

https://en.wikipedia.org/wiki/HTTP_403
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Tuesday, April 3, 2018

Which of these processor architectures have smartphones traditionally used?

Which of these processor architectures have smartphones traditionally used?

  • Pentium
  • Core i7
  • Phenom II
  • ARM

Which of these processor architectures have smartphones traditionally used?

EXPLANATION

Most commonly, mobile devices use Advanced RISC Machine (ARM) CPUs. Core i7, Phenom II, and the older Pentium are used by desktop and laptop computers.
 
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A group of servers that work together to maintain high availability of applications and services is known as a

A group of servers that work together to maintain high availability of applications and services is known as a

  • Fallover Cluster
  • Fallsafe Cluster
  • Failsafe Cluster
  • Failover Cluster 

A group of servers that work together to maintain high availability of applications and services is known as a

EXPLANATION

A failover cluster is a group of servers that work together to maintain high availability of applications and services. If one of the servers, or nodes, fails, another node in the cluster can take over its workload without any downtime (this process is known as failover).
https://technet.microsoft.com/en-us/library/hh831579(v=ws.11).asp
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