Which of the following is both an input and an output device?

Which of the following is both an input and an output device?

• Printer
• Mouse
• USB thumb drive
• Keyboard 

EXPLANATION

a flash drive is an output device.

A flash drive can fit into either category(input, output or storage). It simply depends on how it is used. 

A USB Flash drive is considered a storage medium. Data can be both read, stored, and sent to / from a USB Flash drive, but it does not in itself input or output any data.

 

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Which of the following RAID levels does NOT provide fault tolerance?

Which of the following RAID levels does NOT provide fault tolerance?

• RAID 1
• RAID 0
• RAID 5
• RAID 10 

EXPLANATION

RAID 0 can be used for setups like those big, read-only network file system servers, or if mounting multiple disks is not possible. In RAID 0, data files are broken down into smaller blocks, and each block is written to a separate physical disk drive. This process is known as striping and is called a striped disk array configuration. This can increase I/O performance by spreading the load evenly (more or less) across many drives and channels, so large data can be simultaneously accessed from the different drives and put together quickly, as opposed to a single drive reading a large file one chunk after another. RAID 0 offers great I/0 performance, but has little to no fault tolerance.  

 

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Who can create application data partitions for testing and troubleshooting purposes?

Who can create application data partitions for testing and troubleshooting purposes?

• Domain administrators
• Enterprise administrators
• Database administrators
• Systems administrators 

EXPLANATION

Application Directory Partition
In Windows Server 2003, Active Directory Domain Services support application directory partitions.
Applications and services can use application directory partitions to store application-specific data. Application directory partitions can contain any type of object, except security principals, and can be configured to replicate to any set of domain controllers in the forest.
Unlike a domain partition, an application directory partition is not required to replicate to all domain controllers in a domain and the partition can replicate to domain controllers in different domains of the forest
Application directory partitions are usually created by the applications that will use them to store and replicate data. For testing and troubleshooting purposes, members of the Enterprise Admins group can manually create or manage application directory partitions using the Ntdsutil command-line tool.

 

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What is LDAP?

What is LDAP?

• Lightweight Directory Application Protocol
• Light Directory Access Procedure
• Lightweight Directory Access Protocol
• Lightweight Data Access Protocol 

EXPLANATION

LDAP, Lightweight Directory Access Protocol, is an Internet protocol that email and other programs use to look up information from a server.
LDAP is mostly used by medium-to-large organi­zations. If you belong to one that has an LDAP server, you can use it to look up contact info and the like. Otherwise, if you were just wondering about this acronym, you probably don't need it. But feel free to read on to learn the story of this bit of Internet plumbing.
Every email program has a personal address book, but how do you look up an address for someone who's never sent you email? How can an organization keep one centralized up-to-date phone book that everybody has access to?
Those questions led companies such as Microsoft, IBM, Lotus, and Netscape to support a standard called LDAP. "LDAP-aware" client programs can ask LDAP servers to look up entries in a wide variety of ways. LDAP servers index all the data in their entries, and "filters" may be used to select just the person or group you want, and return just the information you want. For example, here's an LDAP search translated into plain English: "Search for all people located in Chicago whose name contains "Fred" that have an email address. Please return their full name, email, title, and description."
LDAP is not limited to contact information, or even information about people. LDAP is used to look up encryption certificates, pointers to printers and other services on a network, and provide "single sign-on" where one password for a user is shared between many services. LDAP is appropriate for any kind of directory-like information, where fast lookups and less-frequent updates are the norm.
As a protocol, LDAP does not define how programs work on either the client or server side. It defines the "language" used for client programs to talk to servers (and servers to servers, too). On the client side, a client may be an email program, a printer browser, or an address book. The server may speak only LDAP, or have other methods of sending and receiving data—LDAP may just be an add-on method.
If you have an email program (as opposed to web-based email), it probably supports LDAP. Most LDAP clients can only read from a server. Search abilities of clients (as seen in email programs) vary widely. A few can write or update information, but LDAP does not include security or encryption, so updates usually require additional protection such as an encrypted SSL connection to the LDAP server.
If you have OS X and access to an LDAP server, you can enter your LDAP account into System Preferences--Internet Accounts. At bottom of the right pane, click Add Other Account, then choose the LDAP account option. This lets Address Book look up info from your server.
LDAP also defines: Permissions, set by the administrator to allow only certain people to access the LDAP database, and optionally keep certain data private. Schema: a way to describe the format and attributes of data in the server. For example: a schema entered in an LDAP server might define a "groovyPerson" entry type, which has attributes of "instantMessageAddress", and "coffeeRoastPreference". The normal attributes of name, email address, etc., would be inherited from one of the standard schemas, which are rooted in X.500 (see below).
LDAP was designed at the University of Michigan to adapt a complex enterprise directory system (called X.500) to the modern Internet. X.500 is too complex to support on desktops and over the Internet, so LDAP was created to provide this service "for the rest of us."
LDAP servers exist at three levels: There are big public servers, large organizational servers at universities and corporations, and smaller LDAP servers for workgroups. Most public servers from around year 2000 have disappeared, although directory.verisign.com exists for looking up X.509 certificates. The idea of publicly listing your email address for the world to see, of course, has been crushed by spam.
While LDAP didn't bring us the worldwide email address book, it continues to be a popular standard for communicating record-based, directory-like data between programs.

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Which Linux command lists all of the files in a directory, including the hidden ones?

Which Linux command lists all of the files in a directory, including the hidden ones?

• ls -h <directory>
• all-show <directory>
• ls -o <directory>
• ls -a <directory> 

EXPLANATION

ls(1) - Linux man page

Name

ls - list directory contents

Synopsis

ls [OPTION]... [FILE]...

Description

List information about the FILEs (the current directory by default). Sort entries alphabetically if none of -cftuvSUX nor --sort.

Mandatory arguments to long options are mandatory for short options too.

-a, --all

do not ignore entries starting with .

-A, --almost-all

do not list implied . and ..

--author

with -l, print the author of each file

-b, --escape

print octal escapes for nongraphic characters

--block-size=SIZE

use SIZE-byte blocks. See SIZE format below

-B, --ignore-backups

do not list implied entries ending with ~

-c

with -lt: sort by, and show, ctime (time of last modification of file status information) with -l: show ctime and sort by name otherwise: sort by ctime

-C

list entries by columns

--color[=WHEN]

colorize the output. WHEN defaults to 'always' or can be 'never' or 'auto'. More info below

-d, --directory

list directory entries instead of contents, and do not dereference symbolic links

-D, --dired

generate output designed for Emacs' dired mode

-f

do not sort, enable -aU, disable -ls --color

-F, --classify

append indicator (one of */=>@|) to entries

--file-type

likewise, except do not append '*'

--format=WORD

across -x, commas -m, horizontal -x, long -l, single-column -1, verbose -l, vertical -C

--full-time

like -l --time-style=full-iso

-g

like -l, but do not list owner

--group-directories-first

group directories before files.

augment with a --sort option, but any

use of --sort=none (-U) disables grouping

-G, --no-group

in a long listing, don't print group names

-h, --human-readable

with -l, print sizes in human readable format (e.g., 1K 234M 2G)

--si

likewise, but use powers of 1000 not 1024

-H, --dereference-command-line

follow symbolic links listed on the command line

--dereference-command-line-symlink-to-dir

follow each command line symbolic link that points to a directory

--hide=PATTERN

do not list implied entries matching shell PATTERN (overridden by -a or -A)

--indicator-style=WORD

append indicator with style WORD to entry names: none (default), slash (-p), file-type (--file-type), classify (-F)

-i, --inode

print the index number of each file

-I, --ignore=PATTERN

do not list implied entries matching shell PATTERN

-k

like --block-size=1K

-l

use a long listing format

-L, --dereference

when showing file information for a symbolic link, show information for the file the link references rather than for the link itself

-m

fill width with a comma separated list of entries

-n, --numeric-uid-gid

like -l, but list numeric user and group IDs

-N, --literal

print raw entry names (don't treat e.g. control characters specially)

-o

like -l, but do not list group information

-p, --indicator-style=slash

append / indicator to directories

-q, --hide-control-chars

print ? instead of non graphic characters

--show-control-chars

show non graphic characters as-is (default unless program is 'ls' and output is a terminal)

-Q, --quote-name

enclose entry names in double quotes

--quoting-style=WORD

use quoting style WORD for entry names: literal, locale, shell, shell-always, c, escape

-r, --reverse

reverse order while sorting

-R, --recursive

list subdirectories recursively

-s, --size

print the allocated size of each file, in blocks

-S

sort by file size

--sort=WORD

sort by WORD instead of name: none -U, extension -X, size -S, time -t, version -v

--time=WORD

with -l, show time as WORD instead of modification time: atime -u, access -u, use -u, ctime -c, or status -c; use specified time as sort key if --sort=time

--time-style=STYLE

with -l, show times using style STYLE: full-iso, long-iso, iso, locale, +FORMAT. FORMAT is interpreted like 'date'; if FORMAT is FORMAT1<newline>FORMAT2, FORMAT1 applies to non-recent files and FORMAT2 to recent files; if STYLE is prefixed with 'posix-', STYLE takes effect only outside the POSIX locale

-t

sort by modification time

-T, --tabsize=COLS

assume tab stops at each COLS instead of 8

-u

with -lt: sort by, and show, access time with -l: show access time and sort by name otherwise: sort by access time

-U

do not sort; list entries in directory order

-v

natural sort of (version) numbers within text

-w, --width=COLS

assume screen width instead of current value

-x

list entries by lines instead of by columns

-X

sort alphabetically by entry extension

-1

list one file per line

SELinux options:

--lcontext

Display security context. Enable -l. Lines will probably be too wide for most displays.

-Z, --context

Display security context so it fits on most displays. Displays only mode, user, group, security context and file name.

--scontext

Display only security context and file name.

--help

display this help and exit

--version

output version information and exit

SIZE may be (or may be an integer optionally followed by) one of following: KB 1000, K 1024, MB 1000*1000, M 1024*1024, and so on for G, T, P, E, Z, Y.
Using color to distinguish file types is disabled both by default and with --color=never. With --color=auto, ls emits color codes only when standard output is connected to a terminal. The LS_COLORS environment variable can change the settings. Use the dircolors command to set it.

 

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