Linux and Unix systems typically track 3 timestamps in file inodes: atime, ctime, and mtime. The "a" in atime means access. The "m" in mtime means modify. What does the "c" in ctime mean?

Linux and Unix systems typically track 3 timestamps in file inodes: atime, ctime, and mtime. The "a" in atime means access. The "m" in mtime means modify. What does the "c" in ctime mean?

• cache
• create
•  change
• copy-on-write 

 

EXPLANATION

"c" in ctime means change.  Specifically, a change to the inode's status, eg, permissions, ownership, link count, file size, etc.
http://man7.org/linux/man-pages/man7/inode.7.html
"Last status change timestamp (ctime) stat.st_ctime; statx.stx_ctime"

http://www.linux-mag.com/id/8658/
"Timestamps telling when the inode itself was last change (ctime, changing time), the file content was last modified (mtime or modification time), and when the file was last accessed (atime or access time)"

SOURCE

http://man7.org/linux/man-pages/man7/inode.7.html

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When it comes to SNMP technology, what is the range of the "Counter32" parameter?

When it comes to SNMP technology, what is the range of the "Counter32" parameter?

• 0 to 4294967295
• 0 to 1099511627776
• 32 to 272
• -100 to 100 

 

EXPLANATION

The Counter32 class allows all the functionality of unsigned integers but is recognized as a distinct SMI type, which specifies a value that represents a count.
The range is 0 to 4294967295

https://www.webnms.com/snmp/help/snmpapi/snmpv3/using_mibs_in_applns/countr32.html

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What is the fastest back-end database for OpenLDAP ?

What is the fastest back-end database for OpenLDAP ?

• hdb
• sql
• mdb
• bdb 

 

EXPLANATION

• A file with the MDB file extension is a Microsoft Access Database file that literally stands for Microsoft Database. ...
• MDB files contain database queries, tables, and more that can be used to link to and store data from other files, like XML and HTML, and applications, like Excel and SharePoint.

 

http://www.openldap.org/pub/hyc/mdm-paper.pdf

SOURCE

http://www.openldap.org/pub/hyc/mdm-paper.pdf

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Which of these is NOT a use case of Microsoft Azure Stack?

Which of these is NOT a use case of Microsoft Azure Stack?

• Update and extend legacy applications with modern Azure services on-premise
• Address latency and connectivity requirements for edge and disconnected solutions
• Develop applications and deploy in Azure or on-premises to meet regulatory and policy requirements
• The next-gen Hyper-V platform for you to migrate your current workloads on your existing hardware 

EXPLANATION

If you answered "next-gen Hyper-V platform for you to migrate..." then yes you're correct - that is NOT the intended use case of Microsoft Azure Stack.  Microsoft Windows Server Software Defined (WSSD)
is a better solution to implement virtualization in scale within your datacenter.   Azure Stack's three primary use cases can be found at the link provided to learn more.

SOURCE

https://azure.microsoft.com/en-us/overview/azure-stack/

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CPUs have a NX flag/bit to segregate areas of memory for process instruction or data. What does NX stand for?

CPUs have a NX flag/bit to segregate areas of memory for process instruction or data. What does NX stand for?

• NineX
• Non-Existent
• No-Execute
• Near-Exact 

EXPLANATION

The NX bit (no-execute) is a technology used in CPUs to segregate areas of memory for use by either storage of processor instructions (code) or for storage of data, a feature normally only found in Harvard architecture processors. However, the NX bit is being increasingly used in conventional von Neumann architecture processors, for security reasons.
An operating system with support for the NX bit may mark certain areas of memory as non-executable. The processor will then refuse to execute any code residing in these areas of memory. The general technique, known as executable space protection, is used to prevent certain types of malicious software from taking over computers by inserting their code into another program's data storage area and running their own code from within this section; one class of such attacks is known as the buffer overflow attack.
Intel markets the feature as the XD bit (execute disable). Advanced Micro Devices (AMD) uses the marketing term Enhanced Virus Protection (EVP). The ARM architecture refers to the feature, which was introduced in ARMv6, as XN (execute never).[1] The term NX bit itself is sometimes used to describe similar technologies in other processors.

SOURCE

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

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