First, Linux common commands

1.1. System Information

The processor architecture of the Arch Display machine (1)

UNAME-M Display the processor architecture of the machine (2)

Uname-r displaying the kernel version in use

DMIDECODE-Q Display hardware system components-(SMBIOS/DMI)

Hdparm-i/DEV/HDA lists the architecture characteristics of a disk

HDPARM-TT/DEV/SDA performing a test read operation on the disk

Cat/proc/cpuinfo displaying information for CPU info

Cat/proc/interrupts Display Interrupt

Cat/proc/meminfo Verifying memory usage

Cat/proc/swaps shows which swap is used

Cat/proc/version version of the kernel is displayed

Cat/proc/net/dev Display network adapter and statistics

Cat/proc/mounts displaying the loaded file system

Lspci-tv List of PCI devices

LSUSB-TV Display USB Device

Date Displays the system date

Cal 2007 Displays the 2007 calendar table

Date 041217002007.00 sets the day and time of day-the year of the month. seconds

Clock-w saving time changes to the BIOS

1.2. Shutdown (System shutdown, restart, and logout)

SHUTDOWN-H now shut down system (1)

Init 0 Shutdown System (2)

Telinit 0 Shutdown System (3)

Shutdown-hhours:minutes & Shut down the system at a predetermined time

Shutdown-c Cancel the system at a predetermined time

Shutdown-r now restart (1)

Reboot restart (2)

Logout logoff

1.3. Files and directories

Cd/home Enter '/home ' directory '

Cd.. Return to the top level directory

Cd.. /.. Return to the top level two directory

CD into the personal home directory

CD ~user1 into the personal home directory

CD-Return to the last directory

PWD Display work path

ls to view the files in the directory

Ls-f viewing files in a directory

Ls-l displaying details of files and directories

Ls-a Show hidden files

LS *[0-9]* displays filenames and directory names that contain numbers

Tree displays files and directories starting with the root directory (1)

Lstree displaying files and directories starting with the root directory tree (2)

mkdir dir1 Create a directory called ' Dir1 '

mkdir dir1 DIR2 Create two directories at a time

Mkdir-p/tmp/dir1/dir2 Create a directory tree

Rm-f file1 Delete a file called ' File1 '

RmDir dir1 Delete a directory called ' Dir1 '

RM-RF Dir1 Delete a directory called ' Dir1 ' and delete its contents at the same time

RM-RF dir1 DIR2 Delete two directories and their contents at the same time

MV Dir1 New_dir Renaming/Moving a directory

CP file1 file2 Copy a file

CP dir/*. Copy all files under a directory to the current working directory

Cp-a/tmp/dir1. Copy a directory to the current working directory

Cp-a dir1 dir2 Copy a directory

Ln-s file1 lnk1 Create a soft link to a file or directory

ln file1 lnk1 Create a physical link to a file or directory

Touch-t 0712250000 File1 Modify the timestamp of a file or directory-(YYMMDDHHMM)

File file1 outputs themime type of the file as text

Iconv-l List of known encodings

Iconv-f fromencoding-ttoencoding inputfile > OutputFile creates a new from the given input file byassuming it is Enco Ded in fromencoding and converting it to toencoding.

Find. -maxdepth 1-name*.jpg-print-exec convert "{}"-resize 80x60 "thumbs/{}" \; Batch resize files in the current directory and send them to a thumbnailsdirectory (requires convert from Imagemagick)

1.4. File Search

Find/-name file1 from '/' to the root file system to search for files and directories

Find/-user User1 search for files and directories belonging to user ' User1 '

Find/home/user1-name\*.bin searching for files with '. bin ' in directory '/Home/user1 '

Find/usr/bin-type f-atime +100 Search execution files that have not been used in the last 100 days

Find/usr/bin-type f-mtime-10 search for files created or modified within 10 days

Find/-name \*.rpm-execchmod 755 ' {} '; Search for files ending with '. RPM ' and define their permissions

Find/-xdev-name \*.rpm search for files ending with '. RPM ', ignoring removable devices such as optical drives, Czech disks, etc.

Locate \*.ps looking for files ending with '. ps '-run the ' updatedb ' command first

Whereis Halt shows the location of a binary file, source code, or man

Which halt displays the full path of a binary file or executable file

1.5. mount a file system

MOUNT/DEV/HDA2/MNT/HDA2 mount a disk called hda2-ok directory '/mnt/hda2 ' already exists

UMOUNT/DEV/HDA2 unload a disk called Hda2-first from Mount point '/mnt/hda2 ' exit

Fuser-km/mnt/hda2 force unload when the device is busy

Umount-n/mnt/hda2 run unload operation without writing/etc/mtab file-useful when file is read-only or when disk is full

Mount/dev/fd0/mnt/floppy mount a floppy disk

Mount/dev/cdrom/mnt/cdrom mount a CDROM or dvdrom

Mount/dev/hdc/mnt/cdrecorder mount a CDRW or dvdrom

Mount/dev/hdb/mnt/cdrecorder mount a CDRW or dvdrom

Mount-o Loop File.iso/mnt/cdrom mount a file or ISO image file

Mount-t Vfat/dev/hda5/mnt/hda5 to mount a Windows FAT32 file system

Mount/dev/sda1/mnt/usbdisk mount a USB drive or flash device

Mount-t smbfs-ousername=user,password=pass//winclient/share/mnt/share mount a Windows network share

1.6. Disk space

DF-H displays a list of the partitions that are already mounted

LS-LSR |more arranging files and directories in size

Du-sh dir1 estimate directory ' Dir1 ' already used disk space '

Du-sk * | SORT-RN display the size of files and directories in terms of capacity size

Rpm-q-a--qf '%10{size}t%{name}n ' | SORT-K1,1N the space used by the installed RPM package (Fedora,redhat class System) on a per-size basis

dpkg-query-w-f= ' ${installed-size;10}t${package}n ' | SORT-K1,1N Displays the space used by the installed Deb package on a size basis (Ubuntu,debian class System)

Fdisk-l, view the hard disk partition.

1.7. Users and Groups

Groupadd group_name Create a new user group

Groupdel group_name Delete a user group

Groupmod-nnew_group_name Old_group_name Renaming a user group

Useradd-c "Namesurname"-G admin-d/home/user1-s/bin/bash user1 create a user who belongs to the "admin" user group

Useradd User1 create a new user

Userdel-r User1 Delete a user ('-R ' exclude home directory)

Usermod-c "Userftp"-G system-d/ftp/user1-s/bin/nologin user1 modifying user properties

passwd changing passwords

passwd User1 Modify a user's password (root only allowed)

Chage-e 2005-12-31 user1 setting the expiration period for user passwords

Pwck checking the file format and syntax corrections of '/etc/passwd ' and the presence of the user

GRPCK checking the file format and syntax corrections of '/etc/passwd ' and the presence of groups

Newgrp group_name Log in to a new group to change the preset group of newly created files

1.8. Permissions for files

-use "+" to set permissions, use "-" to cancel

LS-LH Display Permissions

ls/tmp | Pr-t5-w$columns the terminal into 5 column display

chmod ugo+rwx Directory1 Set directory owner (U), Group (g), and others (O) to read (R), write (w), and execute (x) permissions

chmod go-rwx directory1 Delete Group (g) Read and write execution permissions to the directory with others (O)

Chown user1 File1 Change the Owner property of a file

Chown-r User1 Directory1 Change the owner property of a directory and change the properties of all files in the directory at the same time

CHGRP group1 file1 Changing a group of files

Chown user1:group1 File1 Changing the owner and group properties of a file

Find/-perm-u+s lists all files in a system that use SUID control

chmod U+s/bin/file1 sets the SUID bit of a binary file-the user who runs the file is also given the same permissions as the owner

chmod u-s/bin/file1 Disables the suid bit for a binary file

chmod G+s/home/public sets the Sgid bit of a directory-similar to suid, but this is a directory-specific

chmod g-s/home/public Disable SGID bit of a directory

chmod O+t/home/public Set the STIKY bit of a file-allow only legitimate owners to delete files

chmod o-t/home/public Disable STIKY bit of a directory

1.9. Special properties of the file

Chattr +a File1 only allowed to read and write files in append mode

Chattr +c File1 allows this file to be automatically compressed/decompressed by the kernel

Chattr +d file1 A file system backup, the DUMP program ignores this file

Chattr +i File1 is set to an immutable file and cannot be deleted, modified, renamed, or linked

Chattr +s File1 allows a file to be safely deleted

Chattr +s File1 Once the application writes to this file, the system immediately writes the result of the modification to the disk

Chattr +u File1 If the file is deleted, the system will allow you to recover the deleted file later.

Lsattr Displaying special properties

1.20. Packaging and compressing files

BUNZIP2 file1.bz2 Extract a file called ' file1.bz2 '

bzip2 file1 compress a file called ' File1 '

Gunzip file1.gz Extract a file called ' file1.gz '

gzip File1 compress a file called ' File1 '

gzip-9 file1 Maximum Compression

RAR a File1.rar test_file create a package called ' File1.rar '

RAR a file1.rar file1file2 dir1 simultaneously compresses ' file1 ', ' file2 ' and directory ' Dir1 '

rar x File1.rar decompression rar Package

Unrar x File1.rar decompression rar Package

TAR-CVF Archive.tarfile1 Create a non-compressed tarball

TAR-CVF archive.tarfile1 file2 dir1 Create a file containing ' file1 ', ' file2 ' and ' Dir1 '

TAR-TF Archive.tar Display the contents of a package

TAR-XVF Archive.tar Release a package

TAR-XVF Archive.tar-c/tmp releasing the compressed package into the/tmp directory

TAR-CVFJ Archive.tar.bz2dir1 Creating a compressed package in BZIP2 format

TAR-XVFJ archive.tar.bz2 extract a compressed package in BZIP2 format

TAR-CVFZ Archive.tar.gzdir1 Create a zipped package in gzip format

TAR-XVFZ archive.tar.gz Unzip a compressed package in gzip format

Zip file1.zip file1 Create a zip-format compression Package

Zip-r file1.zip file1file2 dir1 to compress several files and directories into a zip-format package at the same time

Unzip File1.zip unzip a zip-format tarball

1.21. RPM Package

RPM-IVH package.rpm Installing an RPM package

RPM-IVH--nodeepspackage.rpm Install a RPM package and ignore dependency warnings

Rpm-u package.rpm Update a RPM package without changing its configuration file

Rpm-f package.rpm update one to determine which RPM package is installed

Rpm-e package_name.rpm Delete an RPM package

RPM-QA display all installed RPM packages in the system

Rpm-qa | grep httpd shows all RPM packages with the words "httpd" in their names

Rpm-qi Package_name get special information for an installed package

RPM-QG "Systemenvironment/daemons" shows the RPM package for a component

RPM-QL Package_name displays a list of files provided by an already installed RPM package

RPM-QC Package_name Displays a list of configuration files provided by an already installed RPM package

Rpm-q Package_name--whatrequires Displays a list of dependencies that exist with a RPM package

Rpm-q Package_name--whatprovides shows the volume of a RPM package

Rpm-q package_name--scripts Show scripts executed during installation/removal L

Rpm-q Package_name--changelog shows the revision history of a RPM package

rpm-qf/etc/httpd/conf/httpd.conf confirm which RPM package is provided for the given file

RPM-QP package.rpm-l displays a list of files provided by a RPM package that has not been installed

RPM--import/media/cdrom/rpm-gpg-key Import Public key digital certificate

RPM--checksigpackage.rpm confirming the integrity of a RPM package

RPM-QA Gpg-pubkey confirm the integrity of all RPM packages that have been installed

Rpm-v package_name Check file size, license, type, owner, group, MD5 check, and last modified time

Rpm-va Check all installed RPM packages in the system-use with care

RPM-VP package.rpm confirm that an RPM package is not installed

Rpm2cpio package.rpm |cpio--extract--make-directories *bin* Run executable from an RPM package

rpm-ivh/usr/src/redhat/rpms/' arch '/package.rpm install a built-in package from a RPM source

Rpmbuild--rebuildpackage_name.src.rpm Build a RPM package from a RPM source

1.22. Yum Package Upgrade

Yum install package_name download and install a RPM package

Yum localinstallpackage_name.rpm will install a RPM package and use your own software repository to resolve all dependencies for you

Yum updatepackage_name.rpm updates all installed RPM packages in the current system

Yum Update package_name updates a RPM package

Yum Remove package_name Delete an RPM package

Yum list lists all packages installed in the current system

Yum search package_name searching for packages in RPM repositories

Yum Clean Packages cleanup rpm cache to delete downloaded packages

Yum Clean headers Delete all header files

Yum Clean all deletes all cached packages and header files

1.23. deb Package

Dpkg-i package.deb Install/update a deb Package

Dpkg-r package_name Remove a deb package from the system

DPKG-L display all installed Deb packages in the system

Dpkg-l | grep httpd Displays all the Deb packages with the words "httpd" in their names

Dpkg-s Package_name get information on a special package already installed in the system

Dpkg-l Package_name displays a list of files provided by a Deb package that is already installed in the system

Dpkg--contentspackage.deb shows a list of files provided by a package that has not yet been installed

Dpkg-s/bin/ping confirm which Deb package the given file is provided by

1.24. Apt Software tools

Apt-get installpackage_name Install/update a deb Package

Apt-cdrom installpackage_name Install/update a deb package from CD

Apt-get update packages in the upgrade list

Apt-get Upgrade upgrade all installed software

Apt-get Removepackage_name Remove a deb package from the system

Apt-get Check to verify that the software repositories that are dependent are correct

Apt-get clean the cache from the downloaded package

Apt-cache Searchsearched-package Returns the package name that contains the string you want to search

1.25. View the contents of a file

Cat File1 Viewing the contents of a file starting from the first byte

TAC File1 To reverse view the contents of a file from the last line

More File1 View the contents of a long file

Less file1 is similar to the ' more ' command, but it allows a reverse operation in the same way as a forward operation in a file

Head-2 File1 View the first two lines of a file

Tail-2 File1 View the last two lines of a file

Tail-f/var/log/messages Real-time view of content that is added to a file

1.26. Text Processing

Cat File1 file2 ... | Command <> File1_in.txt_or_file1_out.txt General syntax for textmanipulation using PIPE, STDIN and STDOUT

Cat File1 | Command (Sed,grep, awk, grep, etc ...) > Result.txt Merge the detailed description text of a file and write the introduction to a new file

Cat File1 | Command (Sed,grep, awk, grep, etc ...) >> Result.txt Merge The detailed description text of a file and write the introduction to an existing file

grep aug/var/log/messages Find the keyword "/var/log/messages" in the file '

grep ^aug/var/log/messages in file '/var/log/messages ' to find words that begin with "."

grep [0-9]/var/log/messages selects all rows in '/var/log/messages ' file that contain numbers

grep aug-r/var/log/* searches the directory '/var/log ' and subsequent directories for the string "the"

Sed ' s/stringa1/stringa2/g ' example.txt replace "string1" in Example.txt file with "string2"

Sed '/^$/d ' example.txt remove all blank lines from the Example.txt file

Sed '/*#/d; /^$/d ' Example.txt Remove all comments and blank lines from the Example.txt file

echo ' Esempio ' | TR ' [: Lower:] ' [: Upper:] ' merging upper and lower cell contents

Sed-e ' 1d ' result.txt excluding the first line from the file Example.txt

Sed-n '/stringa1/p ' view lines that contain only the word "string1"

Sed-e ' s/*$//' example.txt remove the last white space character from each line

Sed-e ' s/stringa1//g ' example.txt only removes the word "string1" from the document and retains all remaining

Sed-n ' 1,5p;5q ' example.txt view the contents from the first line to the 5th line

Sed-n ' 5p;5q ' example.txt view line 5th

Sed-e ' s/00*/0/g ' Example.txt replaces multiple zeros with a single 0

Cat-n file1 number of lines to mark a file

Cat Example.txt | awk ' nr%2==1 ' deletes all even lines in the Example.txt file

echo a b C | awk ' {print$1} ' view one row of the first column

echo a b C | awk ' {print$1,$3} ' view the first and third columns of a row

Paste file1 file2 Merge two files or two columns of content

Paste-d ' + ' file1 file2 merge two files or two columns of content, in the middle with "+" distinction

Sort file1 file2 Sorting two contents of a file

Sort File1 File2 | Uniq Remove the set of two files (duplicate lines are retained only one copy)

Sort File1 File2 | Uniq-u Delete the intersection, leaving the other rows

Sort File1 File2 | Uniq-d Remove the intersection of two files (leaving only files that exist in two files)

Comm-1 file1 file2 Compare the contents of two files delete only what ' file1 ' contains

Comm-2 file1 file2 Compare the contents of two files delete only what ' file2 ' contains

comm-3 file1 file2 Compare the contents of two files delete only two files that are common to each other

1.27. character setting and file format conversion

Dos2unix Filedos.txtfileunix.txt Convert the format of a text file from Msdos to Unix

Unix2dos Fileunix.txtfiledos.txt Convert the format of a text file from UNIX to Msdos

Recode. HTML <page.txt > page.html Convert a text file to HTML

Recode-l | More Show all allowable conversion formats

1.28. File System Analysis

Badblocks-v/dev/hda1 Check for bad blocks on disk hda1

FSCK/DEV/HDA1 repairing/Checking the integrity of the Linux file system on the HDA1 disk

FSCK.EXT2/DEV/HDA1 repairing/Checking the integrity of the Ext2 file system on the HDA1 disk

E2FSCK/DEV/HDA1 repairing/Checking the integrity of the Ext2 file system on the HDA1 disk

E2fsck-j/dev/hda1 Repairing/checking the integrity of ext3 file systems on HDA1 disks

FSCK.EXT3/DEV/HDA1 repairing/Checking the integrity of the Ext3 file system on the HDA1 disk

FSCK.VFAT/DEV/HDA1 repairing/Checking the integrity of the FAT file system on the HDA1 disk

FSCK.MSDOS/DEV/HDA1 repairing/Checking the integrity of the DOS file system on the HDA1 disk

DOSFSCK/DEV/HDA1 repairing/Checking the integrity of the DOS file system on the HDA1 disk

1.29. Initializing a file system

MKFS/DEV/HDA1 creating a file system in the HDA1 partition

MKE2FS/DEV/HDA1 creating a Linux ext2 file system in the HDA1 partition

Mke2fs-j/dev/hda1 Create a Linux ext3 (journaled) file system in the HDA1 partition

Mkfs-t vfat 32-f/dev/hda1 Creating a FAT32 file system

Fdformat-n/dev/fd0 formatting a floppy disk

Mkswap/dev/hda3 creating a swap file system

1.30. swap file system

Mkswap/dev/hda3 creating a swap file system

Swapon/dev/hda3 enabling a new swap file system

SWAPON/DEV/HDA2/DEV/HDB3 enable two swap partitions

1.31. Backup

Dump-0aj-f/tmp/home0.bak/home making a full backup of the '/home ' directory

Dump-1aj-f/tmp/home0.bak/home making an interactive backup of the '/home ' directory

Restore-if/tmp/home0.bak Restoring an interactive backup

Rsync-rogpav--delete/home/tmp sync on both sides of the directory

Rsync-rogpav-e ssh--delete/home ip_address:/tmp via SSH channel rsync

RSYNC-AZ-E SSH--deleteip_addr:/home/public/home/local synchronizes a remote directory to a local directory via SSH and compression

RSYNC-AZ-E ssh--delete/home/local ip_addr:/home/public synchronizing the local directory to the remote directory via SSH and compression

DD bs=1m If=/dev/hda |gzip | SSH [email protected]_addr ' dd of=hda.gz ' to perform a backup of the local disk on the remote host via SSH

DD If=/dev/sdaof=/tmp/file1 Backup disk contents to a file

Tar-puf Backup.tar/home/user performs an interactive backup operation on the '/home/user ' directory

(cd/tmp/local/&& tar C.) | ssh-c [email protected]_addr ' cd/home/share/&& tar x-p ' copy a directory content from the remote directory via SSH

(Tar c/home) | SSH [email protected]_addr ' cd/home/backup-home && tar x-p ' copy a local directory in the remote directory via SSH

Tar CF-. | (cd/tmp/backup; tar xf-) copy a directory locally to another location, preserving the original permissions and links

Find/home/user1-name ' *.txt ' | Xargs Cp-av--target-directory=/home/backup/--parents Find and copy all files ending with '. txt ' from a directory to another directory

Find/var/log-name ' *.log ' | Tar CV--files-from=-| bzip2 > log.tar.bz2 Find all files that end with '. Log ' and make a bzip package

DD if=/dev/hdaof=/dev/fd0 bs=512 count=1 do an action to copy the contents of the MBR (Master Boot Record) to a floppy disk

DD If=/dev/fd0of=/dev/hda bs=512 count=1 recover MBR content from a backup that has been saved to a floppy disk

1.31. Disc

Cdrecord-v Gracetime=2dev=/dev/cdrom-eject Blank=fast-force to clear a rewritable disc content

Mkisofs/dev/cdrom >cd.iso Create a CD-ROM ISO image file on disk

Mkisofs/dev/cdrom | Gzip> cd_iso.gz Create a compressed disc ISO image file on disk

Mkisofs-j-allow-leading-dots-r-V "Label CD"-iso-level 4-o./cd.iso data_cd Create an ISO image file for a directory

Cdrecord-vdev=/dev/cdrom Cd.iso burning an ISO image file

GZIP-DC cd_iso.gz |cdrecord dev=/dev/cdrom-burn a compressed ISO image file

Mount-o Loop Cd.iso/mnt/iso mount an ISO image file

Cd-paranoia-b from a CD to the audio track to the WAV file

Cd-paranoia--"-3" from a CD to the audio track to the WAV file (parameter-3)

Cdrecord--scanbus Scan bus to identify SCSI channels

DD IF=/DEV/HDC | md5sum Verifying the md5sum encoding of a device, such as a CD

1.32. Network-(Ethernet and WiFi wireless)

Ifconfig eth0 shows the configuration of an Ethernet card

Ifup eth0 enable a ' eth0 ' network device

Ifdown eth0 Disable a ' eth0 ' network device

Ifconfig eth0 192.168.1.1netmask 255.255.255.0 control IP Address

Ifconfig eth0 promisc set ' eth0 ' into promiscuous mode to sniff packets (sniffing)

Dhclient eth0 enable ' eth0 ' in DHCP mode

Route-n Show Routingtable

Route add-net 0/0 gwip_gateway configura default Gateway

Route add-net 192.168.0.0netmask 255.255.0.0 GW 192.168.1.1 Configure static route to reach network ' 192.168.0.0/16 '

Route del 0/0 gwip_gateway remove static route

echo "1" >/proc/sys/net/ipv4/ip_forward Activate IP routing

Hostname Show hostname Ofsystem

Host Www.example.comlookup hostname To resolve name to IP address and viceversa (1)

Nslookup www.example.comlookup hostname To resolve name to IP address and viceversa (2)

IP link Show show linkstatus of all interfaces

Mii-tool eth0 show Linkstatus of ' eth0 '

Ethtool eth0 Showstatistics of the network card ' eth0 '

Netstat-tup Show allactive Network Connections and their PID

NETSTAT-TUPL Show Allnetwork Services listening on the system and their PID

Tcpdump TCP port ShowAll HTTP traffic

Iwlist Scan Show Wirelessnetworks

Iwconfig eth1 Showconfiguration of a wireless network card

Hostname show hostname

Host Www.example.comlookup hostname To resolve name to IP address and viceversa

Nslookup www.example.comlookup hostname To resolve name to IP address and viceversa

Whois www.example.com lookup on Whois database

First, Linux common commands