When using the esxtop command on an ESXi host, which keyboard button is used to forcefully stop, or kill, a running VM?

When using the esxtop command on an ESXi host, which keyboard button is used to forcefully stop, or kill, a running VM?

• s
• d
• t
• k 

 

EXPLANATION

Pressing 'k' while in the VM view of esxtop will prompt you for the offending VM's WorldID number, which can be found in table below. 

 

The following procedure can be used to kill a VM (The bold text are the commands to enter):

• esxtop
• Press c for the CPU resource screen
• Press shift + V to display VMs only
• Press f to change the display fields 
• Press c to select the LWID (Leader World Id) and press enter
• Identify the VM by it’s LWID
• Press k
• Enter the LWID of the VM to kill and press enter
• Wait for 30 seconds and validate that the VM is no longer listed

 

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In Windows, what is the keyboard command you use to close an active application or shutdown Windows?

In Windows, what is the keyboard command you use to close an active application or shutdown Windows?

• Ctrl+Esc
• Window + L
• Alt +F4
• Ctrl+Alt+Del 

 

EXPLANATION

 

Command	Shortcut	Explanation
Cut	Ctrl+X	Copies and removes an item or text; used with Paste
Copy	Ctrl+C	Copies an item or text; used with Paste
Paste	Ctrl+V	Inserts the last cut or copied item or text
Select All	Ctrl+A	Selects all text or items
Undo	Ctrl+Z	Undoes the last action
Redo	Ctrl+Y	Redoes the last thing undone
Troubleshoot/Force Quit	Ctrl+Alt+Delete	Opens Task Manager (see note)
Close window	Alt+F4	Closes window; shuts down computer if all windows are closed
New	Ctrl+N	Opens a new window, tab, or document
Open	Ctrl+O	Opens a file or document
Save	Ctrl+S	Saves a file
Find	Ctrl+F	Opens search tools; in most programs, opens a search box to find specific words on a page

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Which of the following can use both TCP and UDP?

Which of the following can use both TCP and UDP?

• Telnet
• FTP
• SSL
• DNS

 

EXPLANATION

 The correct answer is TCP- Transfers; UDP- Queries. The DNS uses TCP Port 53 for zone transfers, for maintaining coherence between the DNS database and the server. The UDP protocol is used when a client sends a query to the DNS server. The TCP protocol should not be used for queries as it gives a lot of information, which is useful to attackers. To remember this just note the capitalized letters are unique to each other: Tcp = Transfer and Udp = qUeries.

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What is the frequency range of the IEEE 802.11b standard?

What is the frequency range of the IEEE 802.11b standard?

• 24Gbps
• 5GHz
• 2.4GHz
• 5Gbps 

 

EXPLANATION

802.11b boasts an impressive performance. It is able to transfer data with raw data rates up to 11 Mbps, and has a good range, although not when operating at its full data rate.

Summary of 802.11b Wi-Fi Standard Specification
Parameter	Value
Date of standard approval	July 1999
Maximum data rate (Mbps)	11
Typical data rate (Mbps)	5
Typical range indoors (Metres)	~30
Modulation	CCK (DSSS)
RF Band (GHz)	2.4
Channel width (MHz)	20

When transmitting data 802.11b uses the CSMA/CA technique that was defined in the original 802.11 base standard and retained for 802.11b. Using this technique, when a node wants to make a transmission it listens for a clear channel and then transmits. It then listens for an acknowledgement and if it does not receive one it backs off a random amount of time, assuming another transmission caused interference, and then listens for a clear channel and then retransmits the data.

 

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What was the first search engine on the internet?

What was the first search engine on the internet?

• AltaVista
• Yahoo
• Google
• Archie 

 

EXPLANATION

The first tool used for searching content (as opposed to users) on the Internet was Archie. The name stands for "archive" without the "v". It was created by Alan Emtage, Bill Heelan and J. Peter Deutsch, computer science students at McGill University in Montreal, Quebec, Canada.

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IPv4 uses 32bits. How many bits does IPv6 use?

IPv4 uses 32bits. How many bits does IPv6 use?

• 64
• 256
• 32
• 128 

 

EXPLANATION

The size of an IPv6 address is 128 bits, compared to 32 bits in IPv4. 

The address space therefore has 2¹²⁸ = 340,282,366,920,938,463,463,374,607,431,768,211,456 addresses (approximately 3.4×10³⁸). Some blocks of this space and some specific addresses are reserved for special uses.

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The Oracle database is a ...

The Oracle database is a ...

• Operating System (OS)
• Data Base Management System (DBMS)
• Interpreter
• Compiler 

Difference between MySQL and Oracle

MySQL and Oracle are the two famous relational databases that are used in small and big companies. Although Oracle Corporation supports both databases, they also have a lot of differences. Oracle is the more powerful software in comparison to MySQL. In this section, we are going to compare the differences between MySQL and Oracle database systems based on the various parameters.

What is MySQL?

MySQL is the popular database management system used for managing the relational database. It is open-source database software, which is supported by Oracle Company. It is fast, scalable, and easy to use database management system in comparison with Microsoft SQL Server and Oracle Database. It is commonly used with PHP scripts for creating powerful and dynamic server-side or web-based enterprise applications.

It is developed and supported by the Swedish Company, MySQL AB, and written in C and C++ programming languages. Many small and big companies use MySQL. MySQL supports many Operating Systems like Windows, Linux, MacOS, etc. with C, C++, and Java languages.

Features of MySQL Database

The essential features of the MySQL database are given below:

• MySQL is a relational database management system and easy to use. We can build and interact with MySQL by using only a few simple SQL statements.
• It is secure because passwords are encrypted in MySQL.
• It follows a client /server architecture.
• It is free and open-source.
• It is scalable.
• It allows transactions to be rolled back, commit, and crash recovery.
• It provides high performance, high flexibility, and high productivity.

What is Oracle?

Oracle is a relational database system that provides self-driving, self-securing, self-repairing, and designed to eliminate error-prone manual database management. Oracle is a cross-platform database system which can run on the various operating system. It allows to store and retrieve data quickly and safely. It is available free for the student but cannot use for commercial purposes. It is the first database software developed for business purposes to manipulate data using a query language. Oracle was released in 1980 with basic SQL features. This software is scalable, portable, distributed, and programmable.

Features of Oracle Database

The essential features of an Oracle database are given below:

• Oracle database is a cross-platform because it can run on various operating systems such as Windows, Linux, Mac, etc.
• It supports a logical database structure that allows interacting with the database without knowing the physical storage of your data.
• It is scalable, portable, distributed, and programmable.
• It can handle a large amount of data quickly.
• It supports ACID property that allows us to maintain the integrity and reliability of your data.
• Oracle has networking stacks that enable us to communicate applications across the different platforms with oracle database smoothly.
• It has a recovery manager tool that provides cold, hot, and incremental database backups and recoveries.

MySQL vs. Oracle

Let us summaries the popular differences between MySQL and Oracle in the tabular form given below:

 

Comparison Basis	MySQL	Oracle
Introduction	It is an open-source, cross-platform relational database management system built by Swedish Company MYSQL AB and currently supported by the Oracle.	Oracle is a relational database system (RDBMS) that implements object-oriented features. It allows to store and retrieve data quickly and safely. It can handle a large amount of data.
Release	It was released in 1995.	It was released in 1980.
Cost	It is free and open-source. It is licensed under the GNU.	It is licensed for commercial purposes, but it provides the express edition for free. The express edition is recommended for students only.
Scalability	MySQL database is used for small and big businesses.	Oracle database is used for very large scale deployments.
Data Partitioning	It does not support data partitioning.	It supports data partitioning.
Security	It requires a username, password, and host to access the database.	It requires a username, password, and profile validation to access the database.
System Type	It only works with the static system.	It can work with both static and dynamic systems.
Null Value	MySQL supports the null value.	Oracle does not support the null value.
Character	MySQL support only two characters that are CHAR and VARCHAR.	Oracle supports four different characters that are CHAR, VARCHAR2, NCHAR, and NVARCHAR2.
Backup Mechanism	It offers only two backup mechanisms that are mysqlhotcopy and mysqldump.	It offers many backup mechanisms that are backup, hot backup, import, export, etc.
XML Support	It does not support XML.	It supports XML.
Storage Features	It contains only a few storage features like tablespace, synonym, packages, and many others.	It supports many storage features that are tablespace, synonym, packages, etc.
Locking facility	MySQL has only a table locking facility.	Oracle has table locking as well as a row locking facility.
Language support	MySQL support only SQL language.	Oracle supports both SQL and PL/SQL languages.
Operating System Support	It supports the following Operating System: Windows Mac OS X Linux UNIX z/OS BSD Symbian AmigaOS	It supports the following Operating System: Windows Mac OS X Linux UNIX z/OS

 

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