What is the "Power Good Signal", according to the ATX specification?

What is the "Power Good Signal", according to the ATX specification?

• -5 Volt current the motherboard generates to indicate it's functioning.
• LED power light on the computer indicating proper function
• Means that the power supplied to the computer power supply is ample
• +5 volt signal generated in the power supply that is supplied to the motherboard 

EXPLANATION

The Power Good signal (sometimes called Power_OK or PWR_OK) is a +5 V (nominal) active high signal (with a variation from +2.4 V through +6.0 V generally being considered acceptable) that is supplied to the motherboard when the power supply has passed its internal
self-tests and the output voltages have stabilized. This typically takes place anywhere from 100 ms to 500 ms (0.1–0.5 seconds) after you turn on the power supply switch. The power supply then sends the Power_Good signal to the motherboard, where the processor timer chip that controls the reset line to the processor receives it.

SOURCE

http://www.tomshardware.com/reviews/power-supply-specifications-atx-reference,3061-2.html
https://en.wikipedia.org/wiki/Power_good_signal

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In Group Policy, what is the default order of precedence, (not to be confused with the order in which a policy is processed,) excluding User and Computer accounts, that a policy is applied?

In Group Policy, what is the default order of precedence, (not to be confused with the order in which a policy is processed,) excluding User and Computer accounts, that a policy is applied?

• Domain, Site, OU, Local
• OU, Domain, Site, Local
• Local, Site, Domain, OU
• Site, OU, Domain, Local 

 

EXPLANATION

The order of precedence for Group Policy is:

• OU
• Domain
• Site
• Local

However the order that the Policy is processed is just the opposite:

• Local
• Site
• Domain
• OU

SOURCE

https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2003/cc757050(v=ws.10)

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How could leaving a VMware snapshot unattended cause a server down scenario?

How could leaving a VMware snapshot unattended cause a server down scenario?

• Known bug in ESXi 5.0. VMDK file for VM becomes locked when multiple snapshots exist for the same VM
• All remaining storage space on the host becomes used
• The snapshot becomes "unlocked" and causes a hostname/IP conflict
• Trick question, snapshots are good for as long as you need them 

EXPLANATION

Snapshots grow in size over time.  Although the host and VMs may not actually go down, lack of sufficient space on the host would render the host and all hosted virtual machines nearly useless - similar to a CPU and/or memory utilization being maxed out.  Should this occur, access the vSphere client and delete all snapshots.  If you power down the VM, the process will take longer but you will not be able to power up the VM until the process completes.  Leaving the VM powered on will take longer to delete the snapshot but once sufficient space is gained the server(s) should start normal operation again.
Best practices for virtual machine snapshots in the VMware environment:
https://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&external...

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What does HTTP Error 451 mean?

What does HTTP Error 451 mean?

• Proxy authentication required
• Request timeout
• Unavailable for legal reasons
• Request header fields too large 

EXPLANATION

HTTP 451: Unavailable For Legal Reasons is an error status code of the HTTP protocol that displays when the user requests an illegal resource, such as a web page censored by a government.  Examples of situations where an HTTP 451 error code could be displayed include web pages deemed a danger to national security, or web pages deemed to violate copyright, privacy, blasphemy laws, or any other law or court order.
The number 451 is a reference to Ray Bradbury's 1953 dystopian novel Fahrenheit 451, in which books are outlawed.
https://en.wikipedia.org/wiki/HTTP_451

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What is the purpose of a "Display Server"?

What is the purpose of a "Display Server"?

• To display the I/O logs and communication links between other servers within an infrastructure
• To assist with graphical designers working from low-end devices remotely
• To coordinate the I/O of its clients to and from the rest of the OS, hardware and each other
• To watch movies on during quiet time in an office 

 

EXPLANATION

A display server or window server is a program whose primary task is to coordinate the input and output of its clients to and from the rest of the operating system, the hardware, and each other.

SOURCE

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

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