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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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 

 

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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Which of these processor architectures have smartphones traditionally used?

Which of these processor architectures have smartphones traditionally used?

• Pentium
• Core i7
• Phenom II
• ARM

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 

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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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 

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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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 

 

EXPLANATION

Layer 1 is the physical layer. This layer transmits raw bits and doesn't differentiate them into packets.

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Which of the following file extensions is used by Windows PowerShell script files?

Which of the following file extensions is used by Windows PowerShell script files?

• .ps1
• .cmd
• .shl
• .cpp 

 

EXPLANATION

A PowerShell script is a text file with a .ps1 extension  

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