What is the maximum length specification for unshielded Cat6 cable when used in a 10GBASE-T environment?

What is the maximum length specification for unshielded Cat6 cable when used in a 10GBASE-T environment?

• 328 ft (100m)
• 100 ft (30M)
• 180 ft (55m)
• 365 ft (112m)

EXPLANATION

Category 6 cable (Cat 6), is a standardized twisted pair cable for Ethernet and other network physical layers that is backward compatible with the Category 5/5e and Category 3 cable standards.

Cat 6 has to meet more stringent specifications for crosstalk and system noise than Cat 5 and Cat 5e. The cable standard specifies performance of up to 250 MHz, compared to 100 MHz for Cat 5 and Cat 5e.

Whereas Category 6 cable has a reduced maximum length of 55 meters when used for 10GBASE-T, Category 6A cable is characterized to 500 MHz and has improved alien crosstalk characteristics, allowing 10GBASE-T to be run for the same 100 meter maximum distance as previous Ethernet variants.

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From the old days of DOS, what does the "EMM" in EMM386 stand for?

From the old days of DOS, what does the "EMM" in EMM386 stand for?

• Expanded Memory Manager
• Enhanced Memory Module
• Extended Memory Module
• Executive Memory Mode

EXPLANATION

 EMM386 (software, storage)
An expanded memory manager for IBM PCs with an Intel 80386 or higher processor, part of MS-DOS version 5.00 or higher. EMM386 uses extended memory to simulate expanded memory and also provides upper memory blocks. It must be loaded by a DEVICE= command in your CONFIG.SYS file.

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In Linux system, which file contains the encrypted passwords of the users ?

In Linux system, which file contains the encrypted passwords of the users ?

• /etc/crypttab
• /etc/gshadow
• /etc/shadow
• /etc/password

 

EXPLANATION

In the Linux operating system, a shadow password file is a system file in which encrypted user password are stored so that they aren't available to people who try to break into the system.
Ordinarily, user information, including passwords, is kept in a system file called /etc/passwd.

SOURCE

http://searchsecurity.techtarget.com/definition/shadow-password-file

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In SQL Server, which of the following SQL queries will show the currently installed version of SQL?

In SQL Server, which of the following SQL queries will show the currently installed version of SQL?

• Select version from @@version
• @@version
• Show @@version
• Select @@version 

EXPLANATION

Variables starting @@ are system variables. You need a select to be able to return the value, so the answer is "Select @@version". The other three answers are nonsense, as far as SQL is concerned.

SOURCE

https://www.mssqltips.com/sqlservertip/1140/how-to-tell-what-sql-server-version-you-are-running/

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On an IBM i 7 server, which command do you use to work with active jobs?

On an IBM i 7 server, which command do you use to work with active jobs?

• WRKSYSSTS
• WRKSBS
• WRKACTJOB
• WRKSPLF 

 EXPLANATION

The Work with Active Jobs (WRKACTJOB) command allows you to work with performance and status information for the active jobs in the system.
The sequence of jobs can be changed with the Sequence (SEQ) parameter or through operations on the display. Other parameters allow the selection of jobs to be shown on the display. The selection parameters can also be changed by operations on the display.

SOURCE

http://www.ibm.com/support/knowledgecenter/ssw_ibm_i_73/cl/wrkactjob.htm

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