IT Questions and Answers :)

Friday, March 30, 2018

The physical server that runs the hypervisor is known as the:

The physical server that runs the hypervisor is known as the:

  • Master
  • Trunk
  • Host
  • Root 
The physical server that runs the hypervisor is known as the:

EXPLANATION


A hypervisor is a program that allows multiple operating systems to share a single hardware host. The hypervisor runs on a host server, which is the physical server that provides the resources used these virtual operating systems. https://en.wikipedia.org/wiki/Hypervisor
The term "Host" comes from the biological relationship between a host and a parasite. http://www.businessdictionary.com/definition/host-computer.html
 

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Thursday, March 29, 2018

A device is having a problem accessing the web and internal network via Ethernet. The ticket says it's an OSI layer 1 issue. What is the most reasonable first troubleshooting step to take once you're at the user's desk?

A device is having a problem accessing the web and internal network via Ethernet. The ticket says it's an OSI layer 1 issue. What is the most reasonable first troubleshooting step to take once you're at the user's desk?

  • Make sure the cable is plugged in and has link lights
  • Check the IP address and make sure it is appropriate for the network
  • See if it works in a different browser
  • Make sure the TCP port isn't blocked 

 
A device is having a problem accessing the web and internal network via Ethernet. The ticket says it's an OSI layer 1 issue. What is the most reasonable first troubleshooting step to take once you're at the user's desk?

EXPLANATION

Layer 1 is the physical layer. This layer transmits raw bits and doesn't differentiate them into packets.
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Wednesday, March 28, 2018

Tuesday, March 27, 2018

Which of the following is true of IMAP?

Which of the following is true of IMAP?

  • It uses port 110
  • It sends and receives email
  • It can only be used to send email
  • It leaves messages on the mail server 

Which of the following is true of IMAP?

EXPLANATION

Unlike POP3, IMAP does not directly download and then remove messages from the mail server. Instead, it leaves the email on the server so that messages can be retrieved from various locations. IMAP is used only to retrieve email and uses port 143.
Here is some further discussion about this question

SOURCE


https://www.siteground.com/tutorials/email/pop3-imap-smtp-ports.htm
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Monday, March 26, 2018

What Linux command sets a files permission?

What Linux command sets a files permission?

  • properties
  • rights
  • chmod
  • attrib 
What Linux command sets a files permission?

EXPLANATION


In order to make this practical, a method had to be devised to protect the users from each other. After all, you could not allow the actions of one user to crash the computer, nor could you allow one user to interfere with the files belonging to another user.
This lesson will cover the following commands:
chmod - modify file access rightssu - temporarily become the superuserchown - change file ownershipchgrp - change a file's group ownership

SOURCE

http://linuxcommand.org/lc3_lts0090.php
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Thursday, March 22, 2018

Which of the following does ROBOCOPY stand for?

Which of the following does ROBOCOPY stand for?

  • Recursive File Copy
  • Robust File Copy
  • Read Only Block Option Copy
  • Robot Copy 
Which of the following does ROBOCOPY stand for?

EXPLANATION

ROBOCOPY, or "Robust File Copy", is a command-line directory and/or file replication command

SOURCE

https://en.wikipedia.org/wiki/Robocopy
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Tuesday, March 20, 2018

Which of these is NOT a PHP class?

Which of these is NOT a PHP class?

  • PDO
  • XMLReader
  • ErrorLog
  • DateTime 

 
Which of these is NOT a PHP class?

EXPLANATION

"ErrorLog" is the correct answer.  PHP has a function called "error_log", but it returns true/false and there is no object-oriented version like there is with some of the other classes.
PDO is a PHP extension for working with databases. XMLReader and DateTime are also classes, though they both have procedural versions too.

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Which of these is NOT a utility that lets you create a bootable live USB drive for Linux?

Which of these is NOT a utility that lets you create a bootable live USB drive for Linux?

  • LiveUSB Install
  • UNetbootin
  • GotLive
  • LiLi 
Which of these is NOT a utility that lets you create a bootable live USB drive for Linux?

EXPLANATION

LinuxLive USB Creator (also known as Lili) is a free and open-source software for Windows that can be used to install various Linux compilations, versions and distributions to a USB Flash Drive. The end result is a Bootable Live USB (in some cases with Persistence as well). UNetbootin allows you to create bootable Live USB drives for Ubuntu and other Linux distributions without burning a CD.

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Cloud solutions that can tolerate failures yet still provide service are referred to as what?

Cloud solutions that can tolerate failures yet still provide service are referred to as what?

  • Highly available
  • Highly portable
  • PaaS
  • IaaS 
Cloud solutions that can tolerate failures yet still provide service are referred to as what?

EXPLANATION

High availability ensures that cloud solutions are always accessible. This means eliminating single points of failure, such as storing data on a single hard disk or single network connections.

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What MySQL feature allows for queries to be run periodically in the background, independent of a front-end program?

What MySQL feature allows for queries to be run periodically in the background, independent of a front-end program?

  • MySQL Automatic Events
  • MySQL Task Manager
  • MySQL Event Scheduler
  • MySQL Scheduled Tasks 

 
What MySQL feature allows for queries to be run periodically in the background, independent of a front-end program?

EXPLANATION

The MySQL Event Scheduler allows for queries to be run in the background at scheduled times, either as a one-off or recurring event.

SOURCE

https://dev.mysql.com/doc/refman/5.7/en/events-overview.html
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On a Cisco Catalyst switch, what are the Layer 3 interfaces called that are used to accomplish inter-VLAN routing?

On a Cisco Catalyst switch, what are the Layer 3 interfaces called that are used to accomplish inter-VLAN routing?

  • SVI
  • SIP
  • Trunk interfaces
  • RIP 
On a Cisco Catalyst switch, what are the Layer 3 interfaces called that are used to accomplish inter-VLAN routing?

  EXPLANATION



VLANs divide broadcast domains in a LAN environment. Whenever hosts in one VLAN need to communicate with hosts in another VLAN, the traffic must be routed between them. This is known as inter-VLAN routing. On Catalyst switches it is accomplished by creating Layer 3 interfaces known as Switch Virtual Interfaces (SVI).
Learn more
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By default, which of the following is NOT a legitimate Linux run level?

By default, which of the following is NOT a legitimate Linux run level?

  • 4: Normal mode
  • 6: Reboot system
  • 1: Single-user mode
  • 3: Multi-user mode with networking 
By default, which of the following is NOT a legitimate Linux run level?

EXPLANATION

A Linux run level defines the state of the system after boot. Conventionally, seven run levels exist, numbered from zero to six. They include:
0: Halt system
1: Single-user mode
2: Basic multi-user mode without NFS
3: Multi-user mode with networking
4: Unused
5: Multi-user mode with GUI

6: Reboot system

SOURCE


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What is not true about HSRP?

What is not true about HSRP?

  • Preempt is set by default
  • It is described in RFC 2281
  • Can track an interface for failover
  • Cisco proprietary protocol 
What is not true about HSRP?

 EXPLANATION

Hot Standby Router Protocol (HSRP) is a Cisco proprietary routing protocol that allows host computers on the Internet to use multiple routers that act as a single virtual router, maintaining connectivity even if the first hop router fails, because other routers are on "hot standby" - ready to go. HSRP's preempt has to be manually set with the "standby vlan-number preempt" command in the Vlan interface configuration mode.

SOURCE

http://www.cisco.com/c/en/us/support/docs/ip/hot-standby-router-protocol-hsrp/9234-hsrpguidetoc.html
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Which of the following Powershell commands would give User2 access to User1's calendar? User2 does not currently have access to anything of User1's

Which of the following Powershell commands would give User2 access to User1's calendar? User2 does not currently have access to anything of User1's

  • Add-MailboxFolderPermission -Identity User1@contoso.com:\Calendar -User User2 -AccessRights Owner
  • Set-MailboxFolderPermission -Identity User1@contoso.com:\Calendar -User User2 -AccessRights Owner
  • Add-MailboxPermission -Identity User1@contoso.com:\Calendar -User User2 -AccessRights Owner
  • Set-MailboxPermission -Identity User1@contoso.com:\Calendar -User User2 -AccessRights Owner 
Which of the following Powershell commands would give User2 access to User1's calendar? User2 does not currently have access to anything of User1's

EXPLANATION


There are two things to notice.  First is that you're trying to give new permissions to User2 and not change current permissions of User2 within User1's mailbox.  So we'll want to use Add instead of Set.  Set is used to change permissions if a user already has some sort of permissions within the mailbox.

The second thing is that the calendar is a folder within the mailbox.  We don't want User2 to be able to read User1's emails, so we'll do Add-MailboxFolderPermission instead of Add-MailboxPermission.

SOURCE

https://technet.microsoft.com/en-us/library/dd298062(v=exchg.160).aspx
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Which of these is not a valid option when right clicking a powered on (running) virtual machine in vCenter?

Which of these is not a valid option when right clicking a powered on (running) virtual machine in vCenter?

  • Migrate
  • Rename
  • Clone
  • Remove from Inventory 

Which of these is not a valid option when right clicking a powered on (running) virtual machine in vCenter?

EXPLANATION

You cannot remove a powered on virtual machine from the vCenter inventory.  The VM has to be shut down first.
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A webpage has six images with large margins. These margins cause viewing problems on small screens such as phones. Which css will remove the margins on small devices?

A webpage has six images with large margins. These margins cause viewing problems on small screens such as phones. Which css will remove the margins on small devices?

  • @media screen and (max-width:600;){ img {margin:0px;} }
  • @media screen and (max-width:600px){ #img {margin:0px;} }
  • @media screen and (max-width:600px){ img {margin:0px;} }
  • @media screen and (min-width:600px){ img {margin:0px;} } 

 
A webpage has six images with large margins. These margins cause viewing problems on small screens such as phones. Which css will remove the margins on small devices?

EXPLANATION

img is an HTML tag, so it is referred to without any prefix. #img would be an ID, which can only refer to a single item, so would not be suitable here. (In practice we might use a class though.)
max-width will apply the conditional css to screens of less than the stated width. min-width would affect only larger screens, which is not what we want.
Nasty gotcha: (max-width:600;) is invalid syntax. Although this looks like a standard css statement, it is actually a special comparison clause. It must not be terminated with a semicolon. (Trailing semicolons are optional on single css statements, but for some obscure reason are not allowed here.) 

SOURCE

https://www.w3schools.com/cssref/css3_pr_mediaquery.asp
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When open source software is used in SaaS, it is called ____________ SaaS.

When open source software is used in SaaS, it is called ____________ SaaS.

  • Free
  • Closed
  • Freemium
  • Open
When open source software is used in SaaS, it is called ____________ SaaS.

EXPLANATION

A lot of SaaS services use open source software and are thus called open SaaS services.
 
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What are the three switch port states of the rapid spanning tree protocol (RSTP)?

What are the three switch port states of the rapid spanning tree protocol (RSTP)?

  • Blocking, Learning, Forwarding
  • Disabled, Listening, Forwarding
  • Discarding, Learning, Forwarding
  • Disabled, Blocking, Forwarding 
What are the three switch port states of the rapid spanning tree protocol (RSTP)?

EXPLANATION

There are 3 port states in RSTP (802.1w) that correspond to the three possible operational states. The 802.1D disabled, blocking, and listening states are merged into a unique 802.1w discarding state. The end result is faster reconvergence time. So the three switch port states are:
  • Discarding - No user data is sent over the port
  • Learning - The port is not forwarding frames yet, but is populating its MAC-address-table
  • Forwarding - The port is fully operational

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What cloud computing characteristic ensures services and data are always reachable?

What cloud computing characteristic ensures services and data are always reachable?

  • Integrity
  • Availability
  • Scalability
  • Confidentiality 
What cloud computing characteristic ensures services and data are always reachable?

EXPLANATION


Availability ensures that something is reachable at any time

SOURCE

https://quizlet.com/45222112/comptia-cloud-essentials-certification-practice-questions-flash-cards/
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Which of the following are built-in functions in SQL?

Which of the following are built-in functions in SQL?

  • SUM, AVG, MIN, MAX, MULT
  • SUM, AVG, MULT, DIV, MIN
  • SUM, AVG, MIN, MAX, NAME
  • COUNT, SUM, AVG, MAX, MIN 
 
Which of the following are built-in functions in SQL?
 

EXPLANATION

COUNT, SUM, AVG, MAX, and MIN are all built-in functions in SQL.
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What is a small program or function that automates a specific task called?

What is a small program or function that automates a specific task called?

  • Macro
  • Nano
  • Micro
  • Mongo 
What is a small program or function that automates a specific task called?

 

EXPLANATION


A macro is a small program, or script, that automates common tasks. These scripts are usually run within programs and can often be created by the user. For example, a user might record a macro for Microsoft Word that inserts his entire address when he presses a custom key combination.

SOURCE

https://techterms.com/definition/macro
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How many usable IP addresses are in a single Class C block?

How many usable IP addresses are in a single Class C block?

  • 24
  • 508
  • 36000
  • 254

How many usable IP addresses are in a single Class C block?

EXPLANATION

There are 256 actual addresses, but the 0 and 255 host addresses are not usable, giving you only 254 usable addresses. The .255 is used as the broadcast address, anything sent to that address should be answered by all devices in the same IP Block. The .0 address is reserved as the network address and is not usable as a host address.
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Which of the Following is NOT a Sync Type when Syncing Files and Folders using SyncToy, FreeFileSync and other File Syncing Tools?

Which of the Following is NOT a Sync Type when Syncing Files and Folders using SyncToy, FreeFileSync and other File Syncing Tools?

  • Dedupe
  • Contribute (Update)
  • Sync (Two-Way Sync)
  • Mirror 

 
  Which of the Following is NOT a Sync Type when Syncing Files and Folders using SyncToy, FreeFileSync and other File Syncing Tools?

EXPLANATION

Dedupe is a Storage Technology which operates on a block level to save storage space using pointers to data blocks. It is not a file level operation.
Contribute / Update -> Updates Files from the Left Folder Path to the Right without deleting any files or folders. Renamed, Modified and New Files and Folders are added from Left to Right.
Sync (Two-Way Sync) - New items, Renames, Modifications and Deletions are synced from Left to Right and Right to Left Paths (both directions).
Mirror - Copies and Overwrites all file and folder items from the Left Path to The Right Path - creates a mirror copy from Left to Right File Paths. Useful for Backups to removable storage such as USB External Hard Drives.

SOURCE

https://en.wikipedia.org/wiki/File_synchronization
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Which of the following is NOT an RFID frequency band?

Which of the following is NOT an RFID frequency band?

  • 865-868 MHz
  • 902-928 MHz
  • 470-512 MHz
  • 13.56 MHz 

 
Which of the following is NOT an RFID frequency band?

EXPLANATION




470–512 MHz is in use in the US for low-band TV channels 14–20 (also shared for land mobile 2-way radio use in some areas). https://en.wikipedia.org/wiki/Ultra_high_frequency#United_States
All other frequencies mentioned are used for RFID communication: https://en.wikipedia.org/wiki/Radio-frequency_identification

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What do you call a series of SCSI devices working together through a host adapter?

What do you call a series of SCSI devices working together through a host adapter?

  • An SCSI controller
  • An SCSI chain
  • Cabled SCSI
  • RAID 
  What do you call a series of SCSI devices working together through a host adapter?

EXPLANATION

A series of SCSI devices working together through a host adapter is called an SCSI chain. The host adapter provides the interface between the SCSI chain and the PC.

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If you want to cluster MySQL databases, what software do you use?

If you want to cluster MySQL databases, what software do you use?

  • MySQL Cluster
  • Apache Hadoop
  • Kubernetes
  • Beowulf 
If you want to cluster MySQL databases, what software do you use?

 EXPLANATION

MySQL Cluster provides shared-nothing clustering and auto-sharding for the MySQL database management system. It is designed to provide high availability and high throughput with low latency, while allowing for near linear scalability.

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Which of these is NOT a real Linux package manager?

Which of these is NOT a real Linux package manager?

  • PETget
  • Tuxbrew
  • Conary
  • Pacman 

Which of these is NOT a real Linux package manager?

EXPLANATION


Linux package managers are a dime a dozen and have lots of crazy names, like Pacman, PETget, and Conary.
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For files in Unix and Linux, "atime" means most recent access time. What does "ctime" mean?

For files in Unix and Linux, "atime" means most recent access time. What does "ctime" mean?

  • the time that file was most recently copied
  • the file's data change time
  • the file's status change time
  • the file's creation time 
For files in Unix and Linux, "atime" means most recent access time. What does "ctime" mean?

EXPLANATION

atime is access time, or when the file was last read.
mtime is modification time, or when the file's data was last modified.
ctime is change time, or when the files status (metadata) was last changed.  Metadata, data about the file as opposed to data in the file, is held in the file's inode.
Unix jargon for "the time a file's status last changed". Change time and creation time (ctime)Unix and Windows file systems interpret 'ctime' differently:Unix systems maintain the historical interpretation of ctime as being the time when certain file metadata, not its contents, were last changed, such as the file's permissions or owner (e.g. 'This file's metadata was changed on 05/05/02 12:15pm').    Windows systems use ctime to mean 'creation time'[citation needed] (also called 'birth time') (e.g. 'This file was created on 05/05/02 12:15pm').


SOURCE

https://www.tldp.org/LDP/Linux-Dictionary/html/Linux-Dictionary.html
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Monday, March 19, 2018

What date/time is UNIX time calculated based off of?

What date/time is UNIX time calculated based off of?

  • 00:00:00 31 December 1967
  • 00:00:00 1 January 0000
  • 00:00:00 1 January, 1900
  • 00:00:00 1 January 1970 
 
What date/time is UNIX time calculated based off of?

EXPLANATION

 

Epoch time, also known as Unix time, is defined as the number of seconds that have elapsed since 00:00:00 Coordinated Universal Time (UTC), Thursday, 1 January 1970 (not counting leap seconds).
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Friday, March 16, 2018

Wednesday, March 14, 2018

Why is the Power Factor (PFC) value listed on most modern PSU units?

Why is the Power Factor (PFC) value listed on most modern PSU units?

  • It indicates the level of efficiency of the PSU
  • It points to the materials used in the PSU (Gold, Silver etc)
  • It relates with the thermal resistance properties
  • Indicates coeficient for the longevity of the PSU 

 
Why is the Power Factor (PFC) value listed on most modern PSU units?

EXPLANATION

The Power Factor value shows the efficiency of the power unit. The power unit capabilities are usually stated as W consumed by the unit (kVA). How much of this power will be available to the loads attached to the PSU however is dictated by the its conversion capabilities summarized by the PFC value. For example, a 1000W PSU with a PFC factor of 0.9 will be able to supply a total of 900W to it's loads.


The PFC itself measures the alignment of the the voltage sinusoidal against the current sinusoidal. If they match 100% you would get a PFC of 1 and hence the perfect lossless PSU. In realty >0.95 is hardly achieved and considered very good while 0.8 could be considered as average PSU. 0.7 is considered as a bad performing PSU
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Tuesday, March 13, 2018

Which of the following CLI commands empties the DNS server cache in Windows Server?

Which of the following CLI commands empties the DNS server cache in Windows Server?

  • ipconfig /flushdns
  • Set-DNS -ClearCache
  • Delete-DNSCache
  • dnscmd /clearcache 

 EXPLANATION Dnscmd /clearcache clears the cache used for DNS server. Dnscmd is the tool used to manage DNS from the command line.
ipconfig /flushdns clears the DNS client cache. A DNS server has both caches but the client cache is the one used to provide name resolution for its own requests, not for other clients on the network.
Dnscmd TechNet article:
https://technet.microsoft.com/en-us/library/cc772069(v=ws.11).aspx
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What type of malware replicates itself from PC to PC throughout the network?

What type of malware replicates itself from PC to PC throughout the network?

  • Spyware
  • Scareware/ransomware
  • Trojan
  • Worm

What type of malware replicates itself from PC to PC throughout the network?

EXPLANATION




Computer worms use the network to send copies of themselves to other PCs, usually exploiting a security hole to travel from one host to the next without user intervention. Because they can spread so rapidly across a network infecting every PC in their path, they tend to be the most well-known type of malware, although many users still mistakenly refer to them as viruses.
Trojan horses are applications that look like they are doing something innocuous, but secretly have malicious code that does something else. In many cases, trojans will create a backdoor that allows your PC to be remotely controlled, either directly or as part of a botnet—a network of computers also infected with a trojan or other malicious software. The major difference between a virus and a trojan is that trojans don't replicate themselves—they must be installed by an unwitting user.

Scareware is a relatively new type of attack, where a user is tricked into downloading what appears to be an antivirus application, which then proceeds to tell you that your PC is infected with hundreds of viruses that can only be cleaned if you pay for a full license. Of course, these scareware applications are nothing more than malware that hold your PC hostage until you pay the ransom—in most cases, you can't uninstall them or even use the PC.



Spyware is any software installed on your PC that collects your information without your knowledge, and sends that information back to the creator so they can use it in some nefarious way. This could include keylogging to learn your passwords, watching your searching habits, changing out your browser home and search pages, adding obnoxious browser toolbars, or just stealing your passwords and credit card numbers.
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Monday, March 12, 2018

Revoked digital certificates are listed in a(n)

Revoked digital certificates are listed in a(n)

  • Public Key Crypto Folder (PKCF)
  • Certificate Revocation List (CRL)
  • 509.X certificate
  • Certification Authority Revocation Algorithm (CARA) 
Revoked digital certificates are listed in a(n)

EXPLANATION

n the operation of some cryptosystems, usually public key infrastructures (PKIs), a certificate revocation list (CRL) is a list of certificates
dhruv-k@hcl.com (or more specifically, a list of serial numbers for certificates) that have been revoked, and therefore, entities presenting those (revoked) certificates should no longer be trusted.
https://en.wikipedia.org/wiki/Revocation_list
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Friday, March 9, 2018

What type of jack would you normally use for a POTS line?

What type of jack would you normally use for a POTS line?

  • RJ9
  • RJ31X
  • RJ11
  • RJ45 

 
What type of jack would you normally use for a POTS line?

EXPLANATION

An RJ11 jack supports one POTS (Plain Old Telephone Service) line.
An RJ9 is an unofficial 4P4C plug that is sometimes used for the handset connection to the telephone.  Think the coiled cord. (http://blog.jabra.com/4-types-of-wired-headset-connectors/)
An RJ31X is a special type of jack that can accommodate up to two POTS lines, but is wired using 4 pairs of wire.  This can be described as an intercept or "Man in the Middle" plug.  It is most commonly used with alarm systems,  When the alarm panel is plugged into the jack, the POTS lines pass through the alarm system.  This allow the alarm system to seize the line, possibly dropping a call in progress.  When the alarm system is not plugged into the jack, the POTS lines work normally.

An RJ45 is the jack most IT people are familiar with.  It is the 4 pair plug we normally associate with ethernet and patch cables.

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Thursday, March 8, 2018

In PowerShell, what do you call the method used to pass a hash table to a cmdlet as an argument to give it parameters?

In PowerShell, what do you call the method used to pass a hash table to a cmdlet as an argument to give it parameters?

  • Proping
  • Slamming
  • Hashing
  • Splatting 
 
In PowerShell, what do you call the method used to pass a hash table to a cmdlet as an argument to give it parameters?

EXPLANATION

Splatting can use either an array or a hash table, though it's typically used with a hash table.  The hash table is built with the key names matching the parameter names for the cmdlet, and the values being filled out with the information to pass to the respective parameter.  It's then passed as an argument to the cmdlet with the dollar ("$") decorator replaced with an at symbol ("@").
Example:
$splat = @{
    ParameterOne = 'Value to pass';
    ParameterTwo = 'Another value';
    ParameterThree = 'Still more values';
}

Get-Cmdlet @splat

# The above is equivalent to this:
Get-Cmdlet -ParameterOne 'Value to pass' -ParameterTwo 'Another value' -ParameterThree 'Still more values'
This method can be useful for making a cmdlet with a lot of parameters easier to manage.  It can also be useful for logically adding and removing parameters as needed without having to call the cmdlet multiple times, which can lead to cleaner code and faster execution time.
https://technet.microsoft.com/en-us/library/jj672955.aspx
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Wednesday, March 7, 2018

In SQL, how do you combine the contents of 2 (or more) queries, into a single, combined table without omitting duplicates?

In SQL, how do you combine the contents of 2 (or more) queries, into a single, combined table without omitting duplicates?

  • UNION
  • UNION ALL
  • FULL JOIN
  • JOIN 

 
In SQL, how do you combine the contents of 2 (or more) queries, into a single, combined table without omitting duplicates?

EXPLANATION

The difference between Union and Union all is that Union all will not eliminate duplicate rows, instead it just pulls all rows from all tables fitting your query specifics and combines them into a table. A UNION statement effectively does a SELECT DISTINCT on the results set.
Here's a good, quick resource: http://www.codefari.com/2015/10/what-is-difference-between-union-and.html

SOURCE

http://www.codefari.com/2015/10/what-is-difference-between-union-and.html
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Tuesday, March 6, 2018

Which of the following technologies is required to run Hyper-V on Windows 2012 R2?

Which of the following technologies is required to run Hyper-V on Windows 2012 R2?

  • Hardware Enforced Data Execution Prevention (DEP)
  • Hyper-threading
  • DirectX
  • MMX4 

 
Which of the following technologies is required to run Hyper-V on Windows 2012 R2?

EXPLANATION

Hyper-V virtualization technology requires specific hardware. You can identify systems that support x64-based architecture and Hyper-V by searching the Windows Server Catalog for Hyper-V: Windows Server catalog.
Hyper-V Server has hardware requirements that are similar to those for the Hyper-V role in other editions of Windows Server. Hardware-enforced Data Execution Prevention (DEP) must be available and enabled. Specifically, you must enable the Intel XD (“execute disable”) bit or the AMD NX (“no execute”) bit.

SOURCE

https://technet.microsoft.com/en-us/library/cc731898(v=ws.11).aspx
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Monday, March 5, 2018

In Windows Server, which of the following is NOT a domain-level Flexible Single Master Operation (FSMO) role?

In Windows Server, which of the following is NOT a domain-level Flexible Single Master Operation (FSMO) role?

  • Domain Naming Master
  • Relative ID (RID) Master
  • Infrastructure Master
  • Primary Domain Controller (PDC) Emulator 

EXPLANATION

There are five FSMO Roles represented in a typical Windows Active Directory, three domain-level, two enterprise-level. The forest/enterprise level roles are Schema Master and Domain Naming Master. The domain roles are PDC Emulator, Infrastructure Master, and RID Master.
A more detailed breakdown of FSMO roles can be found here.
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Friday, March 2, 2018

Which of the following is the most common trunking protocol used in virtual LANs?

Which of the following is the most common trunking protocol used in virtual LANs?

  • 802.1t
  • 802.1z
  • 802.1X
  • 802.1Q 
 
Which of the following is the most common trunking protocol used in virtual LANs?

EXPLANATION

IEEE 802.1Q is the networking standard that supports VLANs on an Ethernet network. The standard defines a system of VLAN tagging for Ethernet frames and the accompanying procedures to be used by bridges and switches in handling such frames
 
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Thursday, March 1, 2018

Which one of these is NOT a VoIP protocol?

Which one of these is NOT a VoIP protocol?

  • H.248
  • MXLP
  • SRTP
  • SIP 

 
Which one of these is NOT a VoIP protocol?

EXPLANATION

SIP, SRTP, and H.248 are all valid VoIP proptocols. MXLP, however, just sounds cool.
https://www.packetizer.com/ipmc/papers/understanding_voip/voip_protocols.html

SOURCE

https://www.packetizer.com/ipmc/papers/understanding_voip/voip_protocols.html
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