linux
if the time difference between the provider and consumer is more than 17 minutes off, the ntpd considers this to be what?
"insane" time
Matches an expression if it appears at the end of a line (finding content)
$
which character is used to run programs in the background?
&
Matches any number of characters (finding content)
*
advantages of UEFI over MBR
- no special partitions, all regular - supports much bigger disks (zebibytes bro) - supports up to 128 GPT partitions per disk - provides fault tolerance by storing a copy of the partition table in the first and last sectors on the dsk - GPT performs cyclic redundancy check - assigns unique IDs to each disk and partition
What is the nice value range?
-20 to +19
common apt-get options -d upgrade-install -s all commands -f install remove -q all commands -y all commands --no-upgrade
-d - downloads specified package but doesn't install it -s - stimulates actions associated w/ command but doesn't perform them -f - checks for unmet dependencies, fixing them if possible -q - suppresses progress information -y - sends default yes answer to any prompts displayed in the action -- tells apt-get not to upgrade package if an older version is already installed
cmd w/ rpm to check authenticity of package
-rpm --checksig -package filename here-
cmd w/ rpm to update a package
-rpm -U package_name
cmd w/ rpm to verify a package
-rpm -V package_name
cmd w/ rpm to uninstall package
-rpm -e -package name here-
cmd w/ rpm to install package (local machine)
-rpm -i -package filename here-
cmd w/ rpm to install package from internet
-rpm -i url/filename.rpm
cmd w/ rpm to install package (with progress bar)
-rpm -ihv -package filename here-
cmd w/ rpm to query a package
-rpm -q package_name
what are the 5 types of Linux shells?
-sh (Bourne shell), -bash (bourne-again shell), -csh (c shell), tcsh, and zsh (Z shell)
command used to extract files from tarballs?
-tar -zxvf filename
Matches single character (finding content)
.
This directory contains the executable files necessary to manage and run the linux system.
/bin
this directory contains your bootloader files
/boot
3 different config files for GRUB2
/boot/grub/grub.cfg file files within /etc/grub.d /etc/default/grub
where is the grub config file stored in Fedora?
/boot/grub/grub.conf
where is the grub config file stored in SUSE Linux and debian?
/boot/grub/menu.lst
where are your device filenames stored?
/dev
this directory contains text-based config files used by system as well as services running.
/etc
Contains X window config files (etc)
/etc/X11/
contains a table used to redirect mail to local recipients (etc)
/etc/aliases
this file is used to configure aliases
/etc/aliases
Where are repositories stored for debian?
/etc/apt/sources.list
to specify which users can or cannot create at jobs, edit the following files:
/etc/at.allow and /etc/at.deny
which bash config files contain shell system wide functions and aliases for non-login shells?
/etc/bashrc or /etc/bash.bashrc
where are the config files for CUPS?
/etc/cups/cupsd.conf
what file are all CUPS printers defined in
/etc/cups/printers.conf
config files for adding users
/etc/default/useradd /etc/login.defs /etc/skel
configures file systems to be exported to remote nfs clients (etc)
/etc/exports
Lists the partitions and file systems that will be automatically mounted when the system boots (etc)
/etc/fstab
what file shows a list of all available disk partitions and file systems that can be mounted
/etc/fstab
controls user access to the FTP service running on the system (etc)
/etc/ftpusers
Contains local group definitions (etc)
/etc/group
where are groups defined. and what are fields in order in that file?
/etc/group group, password, GID, and users
Contains a list of hostname-to-IP address mappings the system can use to resolve hostnames
/etc/hosts
a subdirectory that contains startup scripts for services on the system (etc)
/etc/init.d/ or /etc/rc.d/init.d for Fedora or Red hat system.
first runlevel to be executed if not booting in emergency? (File location)
/etc/init.d/boot
contains config parameters for the init process (etc)
/etc/inittab
file that contains a list of all the system libraries; refreshed when the system is initially booted
/etc/ld.so.cache
edit this file to make changes as opposed to direct end of /etc/modprobe.conf
/etc/modprobe.conf.local
what file shows a list of currently mounted filesystems
/etc/mtab
contains your system user accounts
/etc/passwd
default location for local user accounts in linux
/etc/passwd
which bash subdir contain system wide shell environment config parameters for login shells?
/etc/profile and the files in /etc/profile.d
Specifies the DNS server and domain suffix used by the system (etc)
/etc/resolv.conf
maps port numbers to named services on the system (etc)
/etc/services
contains encrypted passwords (etc)
/etc/shadow
what are the config files for yum
/etc/yum.conf /etc/yum.repos.d/
the directory contains subdirectories that serve as home directories for each user account on your linux system
/home
automatic mount points in new distributions start at? (directory)
/media
these directories are used by some linux distributions to mount external devices, including optical drives and \USB drives
/media and /mnt. /mnt is the older directory
this directory contains files for some programs you install on the system
/opt
a pseudo-file system that is dynamically created whenever it's accessed. it's used to access process and other system information from linux kernel.
/proc
any changes made to _______ will be recognized by kernel immediately?
/proc/
this dir is the root user's home dir
/root
this dir contains import system mgmt and admin files
/sbin
this dir contains subdirs where services running on the system save their files
/srv
this dir contains info about the hardware in your system
/sys
this dir contains temporary file created by you or by the system
/tmp
which file systems would I setup on their own partitions in linux?
/tmp, /home, /var
this dir contains application files
/usr
this contains variable data, including your system log files
/var
location of log info for dmesg?
/var/log/dmesg
where are user crontab files stored?
/var/spool/cron/tabs under specified username
where are MTA messages stored in linux?
/var/spool/mail
what are the 7 init run levels?
0 - halt 1 - single-user, rescue/recovery 2 - multi-user, network disabled 3 - multi-user, network enabled 4 - custom 5 - GUI w/ everything else 6 - reboot
which interrupts are hardwired?
0, 1, and 8. System timer, keyboard, and Real-time clock.
what is the default port assignment for DMA controller
0000h or 00C0h
what is the default port assignment for System timer
0040h
What is the default port assignment for keyboard?
0060h
which GRUB2 script is used to set environmental variables?
00_header
the systemd or init process is always assigned what pid?
1
6 lines of a contrab job?
1 - minutes 2 - hour 3 - day 4 - month 5 - day of the week 6 - name of command, including full path, to be run
what are the six fields in /etc/fstab?
1 - specifies the device/partition to be mounted 2 - The dir where the partition is to be mounted 3 - the file system type of the partition 4 - Various mount options 5 - specifies whether file system should be dumped. 6 - specifies order in which fdisk should check the file system at reboot. root partition should be set to 1. others to 2.
what is the ip range for class A ips
1-127 /8
List all steps of installing a linux system
1. conduct needs assessment 2. select distribution 3. verify system requirements and hardware compatibility 4. plan the file system 5. select software packages 6. identify user accounts 7. gather network info 8. select an installation source
which GRUB2 script is used to identify lunix kernels on the root device and create relevant menu entries?
10_linux
how many partitions can GPT hold?
128
what is the ip range for class B ips
128-191 /16
what is the largest partition size that GPT recognizes
18 exabytes
what is the ip range for class C ips
192-223 /24
How many PCI devices can share interrupts
2
what is the largest partition size that mbr recognizes
2 TB
which GRUB2 script uses OS-prober to search for Linux and other operating systems and places the results in the grub2 menu?
30_os-prober
which GRUB2 script is a template for custom menu entries to be inserted into grub.cfg?
40_custom
CUPS supports network printing over what port
631
default permissions for new files?
666 w/ umask 022 = 644 (read and write for owner, and read for group and others)
what do the following SCSI IDs indicate? ID 7 ID 0 or 1 ID 4 or 5
7 - SCSI controllers 0 or 1 - SCSI hard disk drives 4 or 5 - optical drives
default grace period for quotas?
7 days
default permissions for new directories?
777 w/ umask 022 = 755
how many devices do older SCSI controllers support? what about newer ones?
8 devices. 16 devices
which GRUB2 script lets you copy a corresponding part of the grub.cfg file?
90_persistent
default location for Windows domain user accounts
Active Directory
3 phases of linux boot
BIOS, bootloader, and kernel
these scripts are stored in the /etc/init.d dir
BSD
120 mm in diameter and are 1.2 mm thick. capacity of 650-700 MB
CD
which env variable stores the location where your X window display should be sent?
DISPLAY
Tracks are thinner than CD and supports up to 17 GB
DVD
in this type of backup, only the files that have been modified since the last backup are backed up. the files involved are not flagged as having been backed up.
Differential
implemented on motherboard via DCC
Direct memory access channels
used by throughput devices to communicate directly with ram without involving the cpu
Direct memory access channels
which env variable displays the user id of the current user?
EUID
This very fast, flexible file system was created by Silicon Grpahics for its IRIX os
Extents File system (xfs)
uses a memory chip as opposed to optical discs or magnetically encoded platters. can be electronically erased and reprogrammed.
Flash drives
4 types of backup mediums?
Floppy drives, Tape drives, CDs, DVDs
3 types of backup
Full, incremental, Differential
part of the overall unified extensible firmware interface (UEFI) thats designed to replace the BIOS
GPT (GUID partition table)
which bootloader would have to be run upon making changes to the grub mkconfig files for changes to take place?
Grub2
which env variables displays the path to the bash command history file and the number of commands stored in command history file?
HISTFILE and HISTSIZE
Primary type of persistent storage, reads and writes magnetic info from to and from platters.
Hard disk drives
3 components of Drive geometry?
Heads, Cylinders, and Sectors per track
addresses all communications between the devices in the pc and os
I/O
developed by apple, this utility is designed to support high-speed data transfers (up to 3.2 gpbs), not widely implemented, and PnP compatible.
IEEE 1394
what is port 993?
IMAP using TLS/SSL (IMAPS)
in this type of backup, only the files that have been modified since the last backup are backed up. after being backed up, each file is flagged as having been backed up.
Incremental
What are the two choices for installing software on a linux system?
Install from source code (must have compiler installed) or install from package (must have pkg manager such as debian or RPM)
signal sent to CPU to access resources
Interrupt Request Channels
lists directories to look in when trying to locate a shared library (env variable). security risk
LD_LIBRARY_PATH
offers flexibility an efficiency in dealing with constantly changing storage needs
LVM
what are the two commonly implemented database services?
MySQL and PostgreSQL
three entitys dealing with file permissions and ownship
Owner - u or 1 Group - g or 2 others - o or 4
how do we append value to existing variable for the default path?
PATH=$PATH:/var/opt/mydb
What is a process assigned whenever it's created
PID PPID
what is port 995?
POP3 using TLS/SSL (POP3S)
which env variable stores the characters used to create the shell prompt?
PS1
what are the three components of LVM?
Physical volumes (a partition or entire hard disk), Volume groups (one or more physical volumes grouped together), and logical volumes (defined from a volume group)
this type of HDD has one signal path to transmit data serially, bit by bit, and a second serial channel to return receipt acknowledgements to the sender
SATA
what are the two choices of hard disk drives?
SATA and SCSI
what is port 465?
SMTP using TLS/SSL (SMTPS)
defines statements that can be used to retrieve and update data in the database
SQL
the language utilized by services as a means of accessing and manipulating databases
SQL
refers to the number of wedges the platters have been divided into
Sectors per track
this type of drive uses flash memory to store data as opposed to platters, no moving parts. Much more expensive and it's less susceptible to damage from physical impact and quieter moving parts.
Solid-state drives
these scripts are stored in the /etc/rc.d/init.d dir
System V
This utility takes of list of files and copies them into a single archive file (the tar utility)
Tar utility (tape archive)
what are differences between GRUB legacy and GRUB2
The configuration files are stored in different places. Partition numbers start at 1 for GRUB2 instead of 0 for GRUB legacy. GRUB2 can directly read files stored on LVM or RAID devices. The user interface can be translated in GRUB2. GRUB2 includes mechanism for loading modules to support specific features
True or false? the file system must be unmounted before performing a file system check.
True
This is the oldest version of USB, transfers data at a rate of 12 Mbps
USB 1.1
This version USB is fast, and can transfer data at 80 Mbps
USB 2.0
Latest USB version, backwards compatible, and transfers data at up to 5 Gbps
USB 3.0
high-speed removable hardware interface that has pretty much replaced serial, parallel, mouse, and keyboard ports on PC
Universal serial Bus (USB)
this protocol allows you remote access to systems but lacks the security provided by SSH tunneling.
VNC
when are the initrd or initramfs file system dismounted and the ramdisk destroyed?
When linuxrc has finished executing
Matches any single character in range (finding content)
[n-n]
Matches an expression any one character (finding content)
[nnn] [^nnn]
Matches an expression if it appears at the beginning of the line (finding content)
^
what is the difference between a login and non-login session?
a login shell is one that is executed when logging into the system and an non-login shell is typically the root user using the su command or a sysadmin using su to become root.
what is aptitude
a text/menu-based package management tool for debian
what can the cmd dd be utilized for?
allows you to image a disk bit-by-bit
a in vi/vim?
appends after cursor
A in vi/vim?
appends after line
viewing package info w/ debian w/ what cmd
apt-cache
displays all of the package's dependencies w/debian
apt-cache depends [package_name]
checks to see whether or not a package is installed on the system. w/debian
apt-cache pkgnames [package_name]
searches package descriptions for the specifed keyword w/debian
apt-cache search keyword
displays information about the package w/ debian
apt-cache showpkg/show [package_name]
displays the number of packages installed, dependency info, and other package cache info w/ debian
apt-cache stats
reports any missing dependencies in the package cache w/ debian
apt-cache unmet
install packages w/ debian w/ what cmd?
apt-get
verifies the integrity of installed packages as well as the package database w/ debian
apt-get check
removes outdated information from the package database w/ debian
apt-get clean
upgrades all installed packages to the newest version but avoid upgrading packages if the upgrade would break a dependency w/ debian
apt-get dist-upgrade
installs the latest version of a specifed pkg w/ debian
apt-get install
removes specified package w/ debian
apt-get remove
displays updated info about all packages available in your configured package repositories w/ debian
apt-get update
upgrades all installed packages to the newest version w/ debian
apt-get upgrade
if changes are made to sources.list, what cmd should be run?
apt-update sources.list
this daemon can be used to schedule a process to run once sometime in the future
at daemon
this daemon can only schedule a job to run once in the futre
at daemon
Modern distributions implement this service in order to automatically detect when removable media has been inserted
autofs
this command can be used to manipulate output
awk
this command can be used to specify the exact record to match based on a particular pattern
awk
allows for addition of control characters to output
awk - \t - inserts a tab character - \n - adds a new line character - \f - adds a form feed character - \r - adds a carriage return character
this command will move a foreground process to the background
bg
if something is in the foreground and needs to be moved to background?
bg -job number-
these are programs that were originally created as a text file using a programming language.
binary executables
mkfs -b
blocksize
first 440 bytes of mbr are what?
boot file and partitions
what components does the mbr consist of?
boot file, partitions, and partition table
loads operating system into ram
bootloader
executing scripts from command prompt BSD vs System V style?
bsd - /etc/init.d/script_name system v - /etc/rc.d/init.d/script_name
mkfs -i
bytes per inode
which offers most compression but is slower? bzip or gzip
bzip; because it uses a different algorithm
what should you use in shell scripting if you have a condition that can be evaluated to return more than two responses?
case statement; ends w/ esac
command used to configure password aging
chage
C in vi/vim?
change to the end of the line
cc in vi/vim?
changes the whole line
value generated by calculating the contents of a file using MD5 algorithm
checksum
can be used to change the group that owns a file or directory
chgrp
Can be used to change the user or group that owns a file or directory
chown
found in /proc, allows you to list parameters for kernel
cmdline
what is the most common linux printing system?
common unix printing system (CUPS)
after tarball files are extracted, they need to be prepared for compiling using what command?
configure
yy in vi/vim?
copies the line in which cursor is located to the buffer
This utility can be used to create backups like tar, the exception being, a list of files must be generated and passed from standard input in order to create a buckup.
cpio
cmd to restore files from a cpio archive
cpio -iv
mkfs -j
creates journal on the file system
difference between anacron and cron?
cron assumes that the system will remain up and running 24/7 and anacron doesn't make such assumptions.
To run jobs on a regular basis in the future, use this daemon
cron daemon
commands to view and remove a user's crontab?
crontab -l and crontab -r
if something is in the background and needs to be sent to foreground, what interrupt is used?
ctrl-z
5 components of CUPS?
cups scheduler, cups filters, cups backends, postscript printer description (PPD), CUPS web base administration utility
CUPS service is provided by what daemon
cupsd daemon
this command is used to print columns or fields that you specify from a file to the standard output
cut
refers to the concentric parallel tracks on all sides of all platters in the hard disk drive
cylinders
this utility can be used to convert and copy files making a bit-by-bit record of a specified file.
dd
interactive file system debugger
debugfs
d$ in vi/vm?
deletes from the insertion point to the end of line
D in vi/vim?
deletes the rest of the current line from cursor position
dw in vi/vim?
deletes word after cursor including space
de in vi/vm?
deletes word after cursor not including space
this shell command is the 1st step in loading kernel module; creates module.dep file and lists dependencies between modules.
depmod
show info in human-readable format?
df -h
show info in human-readable format and also view the type of file system? (w/ df utility)
df -hT
show inode usage (df)
df -i
show info about the partition a specific file resides on (df)?
df <filename>
Shows where hard drive partitions, optical drives, and other storage devices are mounted in the file system (cmd utility)
df utility
what is the free cmd used for?
displays amount of free and used memory in the system
refers to kernel ring buffer, being able to log everything that occurs during bootprocess.
dmesg
debian packages are installed w/ what command?
dpkg
what is the syntax for installing packages w/ dpkg
dpkg [options] [action] [package-name] or [package-filename]
what is it called when NTP measures and corrects for incidental clock frequency errors
drift
Monitor disk space usage cmd?
du
calculate grand total w/ du?
du -c
Displays lots of user information about ex2/3/4 file systems
dumpe2fs
programmers simply insert links to the functions in these shared libraries in their program code.
dynamic shared libraries
What is LVM used for?
dynamically create/delete more logical volumes, modify size of logical volumes, and create snapshots of volumes.
this utility can be used to restore a damaged superblock on ext2/3/4 file systems
e2fsck
cmd to create disk quotas for your groups?
edquota -g <groupname>
command to edit user quotas?
edquota -u
cmd to create disk quotas for your users?
edquota -u <username>
what is the du cmd used for?
estimates file space usage
similiar to sendmail but easier to configure and manage
exim
true or false? you can't remove a file if you don't have write access to file but you have write access to the directory.
false.
True or false? Linux uses Drive letters.
false. Linux uses virtual file systems and windows uses drive letters.
true or false? fdisk is a utility that supports GPT.
false. fdisk does not support GPT, but gdisk does
true or false? support for xfs is include w/ OpenSUSE and Ubuntu
false. it is included w/ Fedora
true or false? in reference to nice, the lower the number, the lower the priority.
false. the higher the number, the lower the priority
view, create, or delete MBR partitions from command line
fdisk [device] (must be root)
this command will move a background process to the foreground
fg
what needs to be installed before you use locate?
findutils-locate package
cmd used to verify user information
finger [username]
how do floppy drives, optical drives, serial ports, and parallel ports appear in dev
floppy - /dev/fd0 optical - /dev/scd0 or /dev/scd1 serial ports - /dev/ttyS0 parallel port - /dev/lp0
you can use this command to reformat a text file?
fmt
this command displays the amount of free and allocated RAM and swap memory on the linux system
free -m option is used to display memory statistics in mb -t option is used to display tools for each category of information
cmd to perform a file system check?
fsck <device>
if you want persistent mounts for each login, while file should you configure?
fstab
this cmd displays the PIDs of processes using the specified files or file systems.
fuser
dpkg -reconfigure does what?
goes through process of reinstalling an installed package without actually installing. Essentially a repairing mechanism.
ignores case when searching for text (grep function)
grep -i
displays only the names of files that contain the matching text (grep function)
grep -l
displays matching line numbers (grep function)
grep -n
searches recursively through subdirs of path specified (grep function)
grep -r
Displays all lines that do not contain the search string (grep function)
grep -v
if you want disk quota on a disk, what option and field should be specified for quotas?
group quota and user quota in the 4th field
commands used to add, modify, and delete groups in linux
groupadd groupmod groupdel
commands to view which version of grub is being used?
grub-install -v grub2-install -v
what cmd is used to install GRUB bootloader?
grub-install /dev/sda
cmd to encrypt a GRUB password?
grub-md5-crypt. After creating password, place hashed password in grub config file next to password --md5
cmd used to generate grub.cfg?
grub2-mkconfig -o /boot/grub2/grub.cfg
Decompression feature utilized w/ gzip
gunzip
difference between halt and reboot?
halt shuts down the system, and reboot reboots.
a file that points directly to the inode of another file
hard link
what types of quotas can be set on disk?
hard or soft.
what two time sources are used on a linux system
hardware clock (CMOS chip) and system clock (linux kernel)
what are some command line tools that can be used to view information about hardware in system
hdparm /dev/device sg_scan sginfo -l lsusb hwinfo lspci
Refers to the number of read/write heads in a drive
heads
after syncing the system time w/ netdate, what command lets you synchronize the system time w/ your hardware clock
hwclock --systohc
cmd to vew UID of users
id [username]
where is the default runlevel defined?
id:5:initdefault: in /etc/inittab
how can the runlevel be changed at shell prompt?
init -runlevel here-
difference between init 0 and init 6
init 0 - shuts down init 6 - reboots
what process are loaded by the kernel during boot?
init and systemd processes
first process ran on linux after kernel process?
init. when utilizing systemV
virtual file system examples (ramdisk)
initrd, initramfs
stores basic information about a file in the linux file system, including it's size, device, owner, and permissions
inode
mkfs -N
inodes
4 modes of vi/vim?
insert mode, replace mode, command mode, and command-line mode
this shell command loads the actual module
insmod <module_name> (think of it as inserting the module name)
cmds to configure which runlevels are of the init scripts are associated with
insserv and chkconfig
list some of the notable sources you can install linux software from?
install cd/dvd open source project websites rpmfind.net sourceforge.net linux.tucows.com freshmeat.net linux.org
commands that are rolled into the shell program itself
internal shell commands
What is the estimated time difference between the consumer and provider since the last time poll
jitter
this command lets you view all background jobs running on the system
jobs
this command prints a line from each of two specified input files that have identical join fields
join
initializes the basic hardware in your system using the various settings in your BIOS and your CMOS chips
kernel
what two ways are Drivers implemented under linux?
kernel modules and being compiled from source code into kernel
which environmental variable lets you know path for all your libraries? and is a security risk.
ld_library_path
read headers of all libraries found in the /lib, /usr, and any directives include in your /etc.lo.conf and your etc.lo.cash?
ldconfig
lists all shared libraries available on the system
ldconfig -p
lists shared libraries required by a specific application
ldd -v [executable filename]
what was the preferred printing system before CUPS
line printer daemon (LPD)
this command determines the number of lines in a file
ln
index of all files in the file system created in /var/log
locatedb
what concept is used to enable the use of larger hard disks w/ mbr
logical block addressing. involves defining one of four primary partitions as an extended partition, which can hold many logical partitions.
cmd to view printer stats w/ lpd
lpc status
if you have more than CUPS printer connected, what command lets you switch between them
lpoptions -d
cmd to view pending print jobs w/ lpd
lpq
cmd to print a document w/ lpd
lpr -P printername filename
cmd to delete a pending print job from the queue
lprm job_number
what command lets you view CUPS printer information?
lpstat
cmd to display a list of open files belonging to all active processes on the system
lsof -s displays file sizes -t specfies that lsof should produce terse output w/ process identifiers only -u <username> displays only open files associated w/ the specified user
displays devices plugged in, IRQ settings, bus speed of device, and vendor info for device
lspci
command to create LVM logical groups?
lvcreate
this redirects mail addressed to one user to another user's account
mail aliases
the command used to view a list of unread messages w/ qmail?
mailq
executing this command will allow you to read the source code files and generate a compiled executable file
make command
what is the difference between the man and info commands?
man seperates info into pages while info seperates info as nodes.
first 512 bytes of hard drive
mbr
tells system where bootloader resides
mbr
what is globbing
meta characters that can be used to utilize filtering
utility used to make an ext2, ext3, or ext4 file system on a partition
mkfs
utility used to make a Reiser file system on a partition
mkreiserfs /dev/<drive partition>
using this command will format a partition to be used for swap
mkswap
preferred command to install kernel modules
modprobe
what options are used with mount to make a partition read-only or modify?
mount -ro mount -rw
this cmd is used to manually mount a disc
mount -t iso9660 <device> <mount point> mount -t iso9660 /dev/sr0 /media/dvd
0 in vi/vim?
moves the cursor to the start of the current line
runlevel3 equiv in systemd?
multi-user.target or runlevel3.target
to ensure that SQL tables are initialized, what cmd should be run?
mysql_install_db
what command is used to view databases currently running on the server?
mysqlshow
what command can you use to synchronize time on the local system with the time on a time server over the network
netdate
this command must be run to enable mail aliases
newaliases
this utility can be used to launch a program with a different priority level
nice
what command is used to keep a process running after logout?
nohup program & or screen command if installed
what command is run to perform initial synchronization for ntp?
ntpdate address_of_time_provider ntptimeset or rcntp
this command is used to dump a file, including binaries
od (octal dump)
what are the four components of software package?
package name, version number, release number, and arch type
what are the three components of the debian package naming scheme?
packagename, version, and architecture
what is used to restrict access to resources and what file is edited?
pam_limits and /etc/security/limits.conf ulimit command
what utility is used w/ fdish to recognize partition changes without having to reboot
partprobe
combines the functionality of the ps and grep commands
pgrep
To create and mount logical volumes, what order should you create the other volumes?
physical volumes, volume groups, then logical volumes
this makes it possible to use smart cards, proximity cards, biometric readers, etc.
pluggable auth module (PAM)
most popular MTA, easy to configure, and supports sendmail options
postfix
this command is used to format test files for printing
pr
default location for NIS linux accounts (dumb question)
provides centralized user account management
command to create LVM phsyical volumes?
pvcreate <device?
this cmd verifies the existence of user accounts on linux system
pwck
command used to move user password out /etc/passwd into /etc/shadow
pwconv
uses as a replacement for sendmail; modular MTA. built w/ security in mind and functions like postfix
qmail
This utility is used to scan the file system for disk usages as well as to create quota files
quotacheck -a - checks all mounted systems -m - forces checks on mounted file systems -u - checks users -g - checks groups -v - operates in verbose mode
cmd to enable quotas on your file system?
quotaon -av
what are r and x needed for in reference to directories? (in terms of permissions they provide)
r to list the contents, and x to access the contents
what does the following denote? 2&1:
redirects standarderr to standard output default location which is the screen.
differences between grep, egrep, and fgrep
regular grep, extended grep, fgrep obtains patterns from FILE
This is reiser equivalent of the tune2fs utility
reiserfstune
this command can be used to adjust the priority of a process that is currently running?
renice
what is the df cmd used for?
reports file system disk space usage for all mounted file systems
command to display a quota for user?
repquota
cmd to view disk space used by your users?
repquota -av
Verify that grub packages are installed? cmd:
rpm -q grub
command w/rpm used to extract files from packages
rpm2cpio
what is port 636?
secure LDAP
this command is a stream text editor
sed -s replaces instances of a specified text string w/ another text string -d deletes the specified text
the oldest of all MTAs, still default often times and difficult to configure
sendmail
what are the four well known mail transfer agents (MTAs)
sendmail, postfix, qmail, and Exim
these are text files that are executed through the shell itself
shell scripts
what is the uptime cmd used for?
shows how long the cpu is up? resets after reboot.
commands to initiate and cancel a shutdown
shutdown -r shutdown -c
commands to reboot system
shutdown -r, init 6, and telinit
what are the 4 kill terms?
sigterm 15 (default), sigint 2 (ctrl-c), sigkill 9 (killing a stubborn process), sighangup 1 (utilizes same process id)
When time differences between provider and consumer are small, NTP adjust the time on the consumer gradually. what's this called?
slewing
this command sorts the lines of text file alphabetically
sort -f - fold lowercase letters to uppercase -M - sort by month -n - sort numerically -r - reverse order sorting
difference between source, exec, and . commands?
source - executes anything within files; does not create PID exec - takes over PID . - executes anything within files, creates a PID
mkfs -t
specifies the filesystem
this command splits a file into a series of files
split
This stage of GRUB is usually stored in the MBR
stage 1
what are the 3 stages of GRUB legacy
stage 1, stage 1.5, and stage 2
This stage of GRUB is located in the first 30KB of the hard drive immediately after the MBR, but before the first partition.
stage 1.5
This stage of GRUB is stored in a disk partition.
stage 2
to start a utility that you want to be persistent between logins?
start program with no hup or utilize screen utility.
these files are linked statically into the program when it's compiled. the actual code elements for the functions called are integrated directly into the application w/ these files
static shared libraries
how do you turn swap space on? cmd:
swapon
After configuring a swap partition, what command(s) are used to turn it on and off
swapon and swapoff
file that point to anther file in the system and has it's own inode
symbolic link
two types of init scripts?
system V and BSD
3 types of init systems are what?
systemV, upstart, and systemd
view current runlevel in systemd?
systemctl get-default
how to switch targets(runlevels) in systemd?
systemctl isolote runlevel5.target systemctl isolate graphical.target
how to modify default boot target in systemd?
systemctl set-default -boot_target here-
how to stop/start/status/restart services in systemd?
systemctl start/stop/status/restart service.service
An init system used to bootstrap the user space and manage all processes. Introduced in 2010; widely accepted
systemd
what is the systemd grandfather structure from systemd to vi?
systemd process -> login shell -> bash shell -> vi process
installation files used to install source code is typically distributed as what type of file?
tarball file
what utility is used if you need to create/format disc that it is setup to manipulate GUID partition table(GPT)?
terminal utility gdisk
probes for new hardware and loads the appropiate driver modules
the kernel
when time differences between provider and cosumer are relatively large, time adjustments are made more quickly on the consumer
this is called stepping
the last step of BIOs is what?
to locate mbr
what can the set command be used for?
to read and write variables
this command can be used to translate or delete characters
tr -c - use all characters not in X -d - delete characters in X; do not translate -s - replace each input sequence of a repeated character that is listed in X with a single occurrence of that character -t - First truncate X to the length of Y
True or false? most processes running on a linux system will be system processes or daemons
true
true or false? Cron daemon runs continuously in the background.
true
true or false? You can specify actions to follow ctrl-alt-del in /etc/inittab
true
true or false? You can't rename, remove, copy files in a directory if you don't have w access to the directory.
true
true or false? all member of a group share the same permissions.
true
true or false? the make command installs files
true. but only after being a run a second time using the install option.
This utility is used to adjust various file system parameters on ext2/3/4 file systems
tune2fs
this command returns what variant of a command is executed when you enter it
type
creates rules for how devices will be recognized when plugged into the system. stored in /etc/udev/rules.d
udev
What command is used for unmounting partitions?
umount <device>
this command returns information about your linux system using several different options
uname
this command reports or omits repeated lines
uniq
A single bus can include how many devices?
up to 127 devices
Capacity of Blu-ray?
up to 50 GB
linux boot target introduced in the mid-2000s; didn't recieve much fanfare, not widely accepted
upstart
default location for LDAP user accounts
user accounts are stored in a directory service
what five tables are implemented within MySQL
user, db, host, tables_priv, and columns_priv
commands for creating users and editing users
useradd userdel usermod passwd
fields of /etc/passwd file in order
username, password, UID, GID, full_name, home_directory, default_shell
fields of /etc/shadow file in order (8 fields remember)
username, password, last_modified, min_days, max_days, days_warn, disabled_days, expire
what is the syntax for setting the value of a variable?
variable=value
command to create LVM volume groups?
vgcreate
lets you create messages for all users? cmd:
wall
this command prints the number of newlines, words, and bytes in the file
wc
this command locates the source code, binary files, and manual pages for specified files
whereis
the xfs equivalent to tune2fs
xfsadmin
Allows installation of a package and all of its dependencies and it locates packages for you by searching one or more repositories on the internet
yum
Difference between yum downloader and yum?
yum downloader is simpler way of downloading a package without having to install it.
which bash conf files stores user-specific shell preferences for login shells?
~/.bash_profle ~/.bash_login ~/.profile ~/.bash_logout
which bash subdir stores user-specific functions and aliases for non-login shells?
~/.bashrc