What is/was the purpose for using a Dynamic Disk Overlay?

What is/was the purpose for using a Dynamic Disk Overlay?

• Software to increase existing disk drives speed.
• Software to hide a disk drive from hackers.
• A dust cap for the disk drive to be used when cleaning the system.
• Software technique to extend a system BIOS that does not support logical block addressing (LBA). 

 

EXPLANATION

Dynamic drive overlay (DDO, also referred to as: software translation driver) is a software technique to extend a system BIOS that does not support logical block addressing (LBA) to access drives larger than 504 MiB. The technology was continued with similar types of problems up to the LBA-48 extension.

The most widespread vendor for such an extension is the company Ontrack which is licensing its DDO component to several of the major hard disk vendors for integration into their management tools and into their products.
The application of a Dynamic Drive Overlay (DDO), as licensed to Samsung Corporation for example, by Kroll Ontrack's version in their Disk Manager program is for the installation of various hard drives (Ultra/Super IDE/Parallel ATA) in computers that have older BIOS chips that do not recognize hard disk drives larger than 137.4 Gigabytes.[1] The interface is a software program that is loaded at start-up by the computer and augments the BIOS code, thus allowing the system to recognize and read areas of the hard disk drive that normally would not be accessible by the older BIOS.

This technique overrides some of the motherboard BIOS' hard disk controller driver in RAM. To allow access to the full size of any hard disk the software must be loaded before other programs try to access the upper parts of a disk with a critical size. To ensure that this extension gets loaded early most often the boot disk's master boot record is modified and the software installed at the beginning of the disk.

SOURCE

https://en.wikipedia.org/wiki/Dynamic_drive_overlay

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What settings in VMware would you use to keep VMs together or separate?

What settings in VMware would you use to keep VMs together or separate?

• Affinity rules
• NSX
• VDS
• Snapshots 

 

EXPLANATION

An affinity rule is a setting that establishes a relationship between two or more VMware virtual machines (VMs) and hosts.
Affinity rules and anti-affinity rules tell the vSphere hypervisor platform to keep virtual entities together or separated. The rules, which can be applied as either required or preferred, help reduce traffic across networks and keep the virtual workload balanced on available hosts.
If two virtual machines communicate frequently and should share a host, the VMware admin can create a VM-VM affinity rule to keep them together. Conversely, if two resource-hungry VMs would tax a host, an anti-affinity rule will keep those VMs from sharing a host.
Affinity rules and anti-affinity rules can be applied between VMs and hosts as well, and a VM can be subject to VM-VM affinity rules and VM-Host affinity rules at the same time. Affinity and anti-affinity rules in a vSphere environment can conflict with one another. For example, two VMs with an anti-affinity relationship may both be linked to a third VM via an affinity rule, but they cannot share a host. Optional affinity rule violation alarms can alert administrators to these events.

SOURCE

https://searchvmware.techtarget.com/definition/affinity-rules

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In Windows, how do you enter ASCII characters that are not displayed on a keyboard?

In Windows, how do you enter ASCII characters that are not displayed on a keyboard?

Ctrl-Alt + keyboard keys corresponding to ASCII

Alt + ASCII decimal value on number pad

Shift-Alt + keyboard keys cooresponding to ASCII

Alt + ASCII decimal value using keyboard top 

 

EXPLANATION

I have used Alt + ASCI decimal value entered on the number pad for many years for various reasons.  It's a nice way to hide characters in passwords or files you want to keep secure. A password with an Alt-255 (null) character will display as a space and baffle even the most experienced hacker. While working in a public school system, my remote software client was VNC and it stored the password in hexidecimal format in the registry which above average students might
possibly be able to decode. But when ASCII 255 characters are found, they're totally confused. I have also named programs and batch files with just the null character plus extension to make it hidden.  I have also used ASCII extended box and line characters to make things look nicer in batch programs, but is limited with newer versions of Windows that lack ANSI.sys not being standard (it can be enabled).

SOURCE

https://support.office.com/en-us/article/insert-ascii-or-unicode-latin-based-symbols-and-characters-d13f58d3-7bcb-44a7-a4d5-972ee12e50e0

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What do you dial to bring up the IMEI number on a mobile phone?

What do you dial to bring up the IMEI number on a mobile phone?

• #69#*
• *#123#
• *#06#
• #044*# 

EXPLANATION

Every phone or Mobile Broadband device has a unique 15 digit code, called an IMEI number. You might need to find your IMEI number if you want to unlock your device to use with other networks, or for some
insurance policies. You can find your IMEI in the following ways: by entering *#06# on your phone's call screen.

SOURCE

http://support.three.co.uk/SRVS/CGI-BIN/WEBISAPI.dll/,/?New,Kb=Mobile,Ts=Mobile,T=CaseDoc,Case=Obj(6589)

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Which operating system for Exchange 2019 is unsupported:

Which operating system for Exchange 2019 is unsupported:

• Windows Server 2008 R2
• Windows Server 2012 R2
• All of them
• Windows Server 2012 

EXPLANATION

The supported operating system for Exchange 2019 is only Windows Server 2019 Standard or Datacenter. Windows Server 2019 Core edition is
also fully supported and recommended.

SOURCE

https://docs.microsoft.com/en-us/exchange/plan-and-deploy/system-requirements?view=exchserver-2019#operating-system

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In CSS, which one of these symbols is the child selector?

In CSS, which one of these symbols is the child selector?

• -
• +
• >
• ~ 

EXPLANATION

The greater-than symbol ">" is the child selector in CSS and is written between two elements, the first element being the parent and the second element being the child. From the W3Schools website,
"The child selector selects all elements that are the immediate children of a specified element."

SOURCE

https://www.w3schools.com/css/css_combinators.asp

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What is the command to restart IIS services on the command line?

What is the command to restart IIS services on the command line?

• iisrestart
• iisreset
• iisrecycle
• iisrefresh 

EXPLANATION

An IIS server can be restarted without rebooting the entire machine by running the iisreset command on the command line.  There is a button on the IIS management console that can also do this; additionally, you can manually restart the services involved.


Take IISReset as a suite of commands that helps you manage IIS start / stop etc.
Which means you need to specify option (/switch) what you want to do to carry any operation.
Default behavior OR default switch is /restart with iisreset so you do not need to run command twice with /start and /stop.
Hope this clarifies your question. Check this MS DOS help picture you will understand.

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