In SQL, which of the following is the generally preferred way to handle the case where a transaction in progress terminates abnormally?

In SQL, which of the following is the generally preferred way to handle the case where a transaction in progress terminates abnormally?

• Rollforward
• Rollback
• Switch to duplicate database
• Reprocess transactions 

 

EXPLANATION

A transaction is a logical unit of work that contains one or more SQL statements. A transaction is an atomic unit. The effects of all the SQL statements in a transaction can be either all committed (which means that they applied to the database) or all 
rolled back (undone from the database). So, if a transaction terminates abnormally, perform a rollback.

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What VMware vSphere feature allows guest VMs to restart on another host in the event that their host fails?

What VMware vSphere feature allows guest VMs to restart on another host in the event that their host fails?

• DRS
• High availability
• Storage DRS
• Fault tolerance 

 

EXPLANATION

VMware's High Availability (known to us lazy people as HA) allows guest VMs to restart on another host in the event of host failure. For example, if you have two hosts, both with VMs, and the first host has a hardware failure and becomes unresponsive, the VMs that were running on the failed host restart on the other host (provided it has the capacity to run them).
Read more here: https://www.vmware.com/products/vsphere/features/high-availability

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Which of the following is NOT a Linux distro?

Which of the following is NOT a Linux distro?

• BSD
• Ubuntu
• Mint
• Red Hat 

EXPLANATION

Berkeley Software Distribution (BSD) is a Unix operating system derivative developed and distributed by the Computer Systems Research Group 
(CSRG) of the University of California, Berkeley, from 1977 to 1995. Today the term "BSD" is often used non-specifically to refer to any of the BSD descendants which together form a branch of the family ofUnix-like operating systems. Operating systems derived from the original BSD code remain actively developed and widely used.

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By default, what is the lowest permission needed to join computers to an Active Directory domain?

By default, what is the lowest permission needed to join computers to an Active Directory domain?

• Schema Admin
• Domain Admins
• Authenticated Users
• Enterprise Admins 

 

EXPLANATION

By default any Authenticated User can add up to 10 computers to a domain.  The risk with this could be that a user sets up a new workstation and give themselves an admin account on the computer, then add it to the domain using their domain account. 
With these elevated permissions they could do many things.  Most notably, but not limited to, the higher chance of getting a virus on the system to an inexperienced user.

SOURCE

https://technet.microsoft.com/en-us/library/cc976452.aspx

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In Unix systems, what are semaphores?

In Unix systems, what are semaphores?

• A technique for pipeline deletion inside processes
• A technique for coordinating or synchronizing activities
• A technique for pipeline creation inside threads
• A technique for Traffic lights management inside an operating system 

 

EXPLANATION

In programming, especially in Unix systems, semaphores are a technique for coordinating or synchronizing activities in which multiple processes compete for the same operating system resources.
A semaphore is a value in a designated place in operating system (or kernel) storage that each process can check and then change. Depending on the value that is found, the process can use the resource or will find that it is already in use and must wait for some period before trying again. Semaphores can be binary (0 or 1) or can have additional values. Typically, a process using semaphores checks the value and then, if it using the resource, changes the value to reflect this so that subsequent semaphore users will know to wait.
Semaphores are commonly use for two purposes: to share a common memory space and to share access to files. Semaphores are one of the techniques for interprocess communication (IPC). The C programming language provides a set of interfaces or "functions" for managing semaphores.

SOURCE

https://whatis.techtarget.com/definition/semaphore

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With regards to DNS, what is the difference between an A record and an AAAA record?

With regards to DNS, what is the difference between an A record and an AAAA record?

• A record holds one IP for one host and AAAA record can hold up to four IPs for one host
• A record replies to one ping and AAAA record replies to four pings.
• A record is for the A-team and AAAA record is for a squad of A-teams.
• A record holds the IPv4 address and AAAA record holds the IPv6 address 

EXPLANATION

An A and AAAA record are both primary DNS records.  They associate a host name with a specific IP address, so that when a user types in a web address, their browser knows where to go for the actual website. An A record holds the IPv4 address and an AAAA record holds the IPv6 address.
More info here - https://en.wikipedia.org/wiki/List_of_DNS_record_types

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What of the following names is a USB device that registers itself as a network adapter but is a covert systems administration and penetration testing tool?

What of the following names is a USB device that registers itself as a network adapter but is a covert systems administration and penetration testing tool?

• NET Ninja
• BeamGun
• Rubber Ducky
• LAN Turtle 

EXPLANATION

The LAN Turtle is a covert Systems Administration and Penetration Testing tool providing stealth remote access, network intelligence gathering, and man-in-the-middle monitoring capabilities.
Housed within a generic "USB Ethernet Adapter" case, the LAN Turtle’s covert appearance allows it to blend into many IT environments.
See: https://lanturtle.com/ for more information

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