linux命令｜Linux Commands Line（转载）

旧城等待， 2022-08-25 10:50 214阅读 0赞

http://www.linuxguide.it/linux\_commands\_line\_en.htm  
The most complete and updated list of commands on linux by LinuxGuide.it - over 350 commands!

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 <td>&nbsp;</td> 
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 <td>&nbsp;</td> 
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 <td>COMMAND</td> 
 <td>DESCRIPTION</td> 
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 <td colspan="2">&nbsp;</td> 
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 <td colspan="2">System information</td> 
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 <td>arch</td> 
 <td>show architecture of machine</td> 
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 <td>uname -r</td> 
 <td>show used kernel version</td> 
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 <td>dmidecode -q</td> 
 <td>show hardware system components - (SMBIOS / DMI)</td> 
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 <td>hdparm -i /dev/hda</td> 
 <td>displays the characteristics of a hard-disk</td> 
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 <td>hdparm -tT /dev/sda</td> 
 <td>perform test reading on a hard-disk</td> 
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 <td>cat /proc/cpuinfo</td> 
 <td>show information CPU info</td> 
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 <td>cat /proc/interrupts</td> 
 <td>show interrupts</td> 
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 <td>cat /proc/meminfo</td> 
 <td>verify memory use</td> 
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 <td>cat /proc/swaps</td> 
 <td>show file(s) swap</td> 
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 <td>cat /proc/version</td> 
 <td>show version of the kernel</td> 
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 <td>cat /proc/net/dev</td> 
 <td>show network adpters and statistics </td> 
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 <td>cat /proc/mounts</td> 
 <td>show mounted file system(s)</td> 
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 <td>lspci -tv</td> 
 <td>display PCI devices</td> 
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 <td>lsusb -tv</td> 
 <td>show USB devices</td> 
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 <td>date</td> 
 <td>show system date</td> 
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 <td>cal 2007</td> 
 <td>show the timetable of 2007</td> 
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 <td>date 041217002007.00&nbsp;</td> 
 <td>set date and time - MonthDayhoursMinutesYear.Secondi</td> 
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 <td>clock -w </td> 
 <td>save changes on BIOS</td> 
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 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
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 <td colspan="2"> Shutdown, Restart of a system and Logout </td> 
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 <td>shutdown -h now</td> 
 <td>shutdown system</td> 
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 <td>init 0 </td> 
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 <td>shutdown -r hours:minutes &amp;</td> 
 <td>planned shutdown of the system</td> 
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 <td>shutdown -c</td> 
 <td>cancel a planned shutdown of the system</td> 
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 <td>shutdown -r now</td> 
 <td>reboot</td> 
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 <td>reboot</td> 
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 <td>logout</td> 
 <td>leaving session</td> 
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 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
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 <td colspan="2"> Files and Directory </td> 
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 <td>cd /home</td> 
 <td>enter to directory '/ home'</td> 
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 <td>cd ..</td> 
 <td>go back one level</td> 
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 <td>cd ../..</td> 
 <td>go back two levels</td> 
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 <td>cd</td> 
 <td>go to home directory</td> 
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 <td>cd ~utente</td> 
 <td>go to home directory</td> 
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 <td>cd -</td> 
 <td>go to previous directory</td> 
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 <td>pwd</td> 
 <td>show the path of work directory</td> 
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 <td>ls</td> 
 <td>view files of directory</td> 
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 <td>ls -F</td> 
 <td>view files of directory</td> 
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 <td>ls -l</td> 
 <td>show details of files and directory</td> 
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 <td>ls -a</td> 
 <td>show hidden files</td> 
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 <td>ls *[0-9]*</td> 
 <td>show files and directory containing numbers</td> 
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 <td>lstree</td> 
 <td>show files and directories in a tree starting from root</td> 
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 <td>mkdir dir1</td> 
 <td>create a directory called 'dir1'</td> 
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 <td>mkdir dir1 dir2</td> 
 <td>create two directories simultaneously</td> 
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 <td>mkdir -p /tmp/dir1/dir2</td> 
 <td>create a directory tree</td> 
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 <td>rm -f file1</td> 
 <td>delete file called 'file1'</td> 
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 <td>rmdir dir1 </td> 
 <td>delete directory called 'dir1'</td> 
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 <td>rm -rf dir1</td> 
 <td>remove a directory called 'dir1' and contents recursively</td> 
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 <td>rm -rf dir1 dir2</td> 
 <td>remove two directories and their contents recursively</td> 
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 <td>mv dir1 new_dir</td> 
 <td>rename / move a file or directory </td> 
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 <td>cp file1 file2</td> 
 <td>copying a file</td> 
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 <td>cp dir/* .</td> 
 <td>copy all files of a directory within the current work directory</td> 
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 <td>cp -a /tmp/dir1 .</td> 
 <td>copy a directory within the current work directory</td> 
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 <td>cp -a dir1 dir2</td> 
 <td>copy a directory</td> 
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 <td>ln -s file1 lnk1&nbsp;</td> 
 <td>create a symbolic link to file or directory</td> 
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 <td>ln file1 lnk1</td> 
 <td>create a physical link to file or directory</td> 
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 <td>touch -t 0712250000 fileditest</td> 
 <td>modify timestamp of a file or directory - (YYMMDDhhmm)</td> 
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 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
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 <td colspan="2"> File search </td> 
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 <td>find / -name file1</td> 
 <td>search file and directory into root filesystem from '/'</td> 
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 <td>find / -user user1</td> 
 <td>search files and directories belonging to 'user1'</td> 
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 <td>find /home/user1 -name *.bin</td> 
 <td>search files with '. bin' extension within directory '/ home/user1'&nbsp;</td> 
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 <td>find /usr/bin -type f -atime +100</td> 
 <td>search bynary files are not used in the last 100 days</td> 
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 <td>find /usr/bin -type f -mtime -10</td> 
 <td>search files created or changed within 10 days</td> 
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 <td>find / -name *.rpm -exec chmod 755 {} ;</td> 
 <td>search files with '.rpm' extension and modify permits</td> 
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 <td>find / -name *.rpm -xdev</td> 
 <td>search files with&nbsp; '.rpm' extension ignoring removable partitions as cdrom, pen-drive, etc.…</td> 
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 <td>locate *.ps</td> 
 <td>find files with the '.ps' extension - first run 'updatedb' command</td> 
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 <td>whereis halt</td> 
 <td>show location of a binary file, source or man</td> 
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 <td>which halt</td> 
 <td>show full path to a binary / executable</td> 
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 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
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 <td colspan="2"> Mounting a Filesystem </td> 
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 <td>mount /dev/hda2 /mnt/hda2</td> 
 <td>mount disk called hda2 - verify existence of the directory '/ mnt/hda2'</td> 
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 <td>umount /dev/hda2</td> 
 <td>unmount disk called hda2 - exit from mount point '/ mnt/hda2' first</td> 
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 <td>fuser -km /mnt/hda2</td> 
 <td>force umount when the device is busy</td> 
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 <td>umount -n /mnt/hda2</td> 
 <td>run umount without writing the file /etc/mtab - useful when the file is read-only or the hard disk is full</td> 
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 <td>mount /dev/fd0 /mnt/floppy</td> 
 <td>mount a floppy disk</td> 
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 <td>mount /dev/cdrom /mnt/cdrom</td> 
 <td>mount a cdrom / dvdrom</td> 
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 <td>mount /dev/hdc /mnt/cdrecorder</td> 
 <td>mount a cdrw / dvdrom</td> 
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 <td>mount /dev/hdb /mnt/cdrecorder</td> 
 <td>mount a cdrw / dvdrom</td> 
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 <td>mount -o loop file.iso /mnt/cdrom</td> 
 <td>mount a file or iso image</td> 
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 <td>mount -t vfat /dev/hda5 /mnt/hda5</td> 
 <td>mount a Windows FAT32 file system</td> 
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 <td>mount /dev/sda1 /mnt/usbdisk</td> 
 <td>mount a usb pen-drive or flash-drive</td> 
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 <td>mount -t smbfs -o username=user,password=pass //winclient/share /mnt/share</td> 
 <td>mount a windows network share</td> 
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 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
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 <td colspan="2"> Disk Space </td> 
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 <td>df -h</td> 
 <td>show list of partitions mounted</td> 
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 <td>ls -lSr |more</td> 
 <td>show size of the files and directories ordered by size</td> 
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 <td>du -sh dir1</td> 
 <td>estimate space used by directory 'dir1'</td> 
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 <td>du -sh * | sort -rn&nbsp;</td> 
 <td>show size of the files and directories sorted by size</td> 
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 <td>rpm -q -a --qf '%10{SIZE}/t%{NAME}/n' | sort -k1,1n</td> 
 <td>show space used by rpm packages installed sorted by size (fedora, redhat and like)</td> 
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 <td>dpkg-query -W -f='${Installed-Size;10}/t${Package}/n' | sort -k1,1n</td> 
 <td>show space used by deb packages installed sorted by size (ubuntu, debian and like)</td> 
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 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
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 <td colspan="2"> Users and Groups </td> 
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 <td>groupadd group_name</td> 
 <td>create a new group</td> 
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 <td>groupdel group_name</td> 
 <td>delete a group</td> 
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 <td>groupmod -n new_group_name old_group_name</td> 
 <td>rename a group</td> 
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 <td>useradd -c "Nome Cognome" -g admin -d /home/user1 -s /bin/bash user1</td> 
 <td>create a new user belongs "admin" group</td> 
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 <td>useradd user1</td> 
 <td>create a new user</td> 
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 <td>userdel -r user1</td> 
 <td>delete a user ( '-r' eliminates home directory)</td> 
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 <td>usermod -c "User FTP" -g system -d /ftp/user1 -s /bin/nologin user1</td> 
 <td>change user attributes</td> 
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 <td>passwd</td> 
 <td>change password</td> 
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 <td>passwd user1</td> 
 <td>change a user password (only by root)</td> 
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 <td>chage -E 2005-12-31 user1</td> 
 <td>set deadline for user password</td> 
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 <td>pwck</td> 
 <td>check correct syntax and file format of '/etc/passwd'&nbsp; and users existence</td> 
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 <td>grpck</td> 
 <td>check correct syntax and file format of '/etc/group'&nbsp; and groups existence</td> 
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 <td>newgrp group_name</td> 
 <td>log in to a new group to change default group of newly created files</td> 
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 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
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 <td colspan="2"> Permits on File - use "+" to set permissions and "-" to remove </td> 
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 <td>ls -lh</td> 
 <td>show permits</td> 
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 <td>ls /tmp | pr -T5 -W$COLUMNS</td> 
 <td>divide terminal into 5 columns</td> 
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 <td>chmod ugo+rwx directory1</td> 
 <td>set permissions reading (r), write (w) and (x) access to users owner (u) group (g) and others (o)</td> 
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 <td>chmod go-rwx directory1</td> 
 <td>remove permits reading (r), write (w) and (x) access to users group (g) and others (or</td> 
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 <td>chown user1 file1</td> 
 <td>change owner of a file</td> 
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 <td>chown user1 -R directory1</td> 
 <td>change user owner of a directory and all the files and directories contained inside</td> 
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 <td>chgrp gruppo1 file1</td> 
 <td>change group of files</td> 
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 <td>chown user1:gruppo1 file1</td> 
 <td>change user and group ownership of a file</td> 
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 <td>find / -perm -u+s</td> 
 <td>view all files on the system with SUID configured</td> 
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 <td>chmod u+s /bin/file_eseguibile</td> 
 <td>set SUID bit on a binary file - the user that running that file gets same privileges as owner</td> 
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 <td>chmod u-s /bin/file_binario</td> 
 <td>disable SUID bit on a binary file</td> 
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 <td>chmod g+s /home/public</td> 
 <td>set SGID bit on a directory - similar to SUID but for directory</td> 
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 <td>chmod g-s /home/public</td> 
 <td>disable SGID bit on a directory</td> 
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 <td>chmod o+t /home/comune</td> 
 <td>set STIKY bit on a directory - allows files deletion only to legitimate owners</td> 
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 <td>chmod o-t /home/comune</td> 
 <td>disable STIKY bit on a directory</td> 
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 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
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 <td colspan="2">Special Attributes on file - use "+" to set permissions and "-" to remove </td> 
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 <td>chattr +a file1</td> 
 <td>allows write opening of a file only append mode</td> 
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 <td>chattr +c file1</td> 
 <td>allows that a file is compressed / decompressed automatically by the kernel</td> 
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 <td>chattr +d file1</td> 
 <td>makes sure that the program ignores Dump the files during backup</td> 
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 <td>chattr +i file1</td> 
 <td>makes it an immutable file, which can not be removed, altered, renamed or linked</td> 
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 <td>chattr +s file1</td> 
 <td>allows a file to be deleted safely</td> 
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 <td>chattr +S&nbsp; file1</td> 
 <td>makes sure that if a file is modified changes are written in synchronous mode as with sync</td> 
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 <td>chattr +u file1</td> 
 <td>allows you to recover the contents of a file even if it is canceled</td> 
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 <td>lsattr</td> 
 <td>show specials attributes</td> 
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 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
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 <td colspan="2"> Archives and compressed files </td> 
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 <td>bunzip2 file1.bz2</td> 
 <td>decompress a file called 'file1.bz2'</td> 
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 <td>bzip2 file1</td> 
 <td>compress a file called 'file1'</td> 
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 <td>gunzip file1.gz</td> 
 <td>decompress a file called 'file1.gz'</td> 
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 <td>gzip file1</td> 
 <td>compress a file called 'file1'</td> 
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 <td>gzip -9 file1</td> 
 <td>compress with maximum compression</td> 
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 <td>rar a file1.rar test_file</td> 
 <td>create an archive rar called 'file1.rar'</td> 
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 <td>rar a file1.rar file1 file2 dir1</td> 
 <td>compress 'file1', 'file2' and 'dir1' simultaneously</td> 
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 <td>rar x file1.rar</td> 
 <td>decompress rar archive</td> 
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 <td>unrar x file1.rar</td> 
 <td>decompress rar archive</td> 
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 <td>tar -cvf archive.tar file1</td> 
 <td>create a uncompressed tarball</td> 
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 <td>tar -cvf archive.tar file1 file2 dir1</td> 
 <td>create an archive containing 'file1', 'file2' and 'dir1'</td> 
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 <td>tar -tf archive.tar</td> 
 <td>show contents of an archive</td> 
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 <td>tar -xvf archive.tar</td> 
 <td>extract a tarball</td> 
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 <td>tar -xvf archive.tar -C /tmp</td> 
 <td>extract a tarball into / tmp</td> 
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 <td>tar -cvfj archive.tar.bz2 dir1</td> 
 <td>create a tarball compressed into bzip2</td> 
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 <td>tar -xvfj archive.tar.bz2</td> 
 <td>decompress a compressed tar archive in bzip2</td> 
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 <td>tar -cvfz archive.tar.gz dir1</td> 
 <td>create a tarball compressed into gzip</td> 
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 <td>tar -xvfz archive.tar.gz</td> 
 <td>decompress a compressed tar archive in gzip</td> 
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 <td>zip file1.zip file1</td> 
 <td>create an archive compressed in zip</td> 
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 <td>zip -r file1.zip file1 file2 dir1</td> 
 <td>compress in zip several files and directories simultaneously</td> 
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 <td>unzip file1.zip</td> 
 <td>decompress a zip archive</td> 
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 <td colspan="2"> RPM Packages - Fedora, Red Hat and like </td> 
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 <td>rpm -ivh package.rpm</td> 
 <td>install a rpm package</td> 
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 <td>rpm -ivh --nodeeps package.rpm</td> 
 <td>install a rpm package ignoring dependencies requests</td> 
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 <td>rpm -U package.rpm</td> 
 <td>upgrade a rpm package without changing configuration files</td> 
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 <td>rpm -F package.rpm</td> 
 <td>upgrade a rpm package only if it is already installed</td> 
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 <td>rpm -e package_name.rpm</td> 
 <td>remove a rpm package</td> 
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 <td>rpm -qa</td> 
 <td>show all rpm packages installed on the system</td> 
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 <td>rpm -qa | grep httpd</td> 
 <td>show all rpm packages with the name "httpd"</td> 
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 <td>rpm -qi package_name</td> 
 <td>obtain information on a specific package installed</td> 
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 <td>rpm -qg "System Environment/Daemons"</td> 
 <td>show rpm packages of a group software</td> 
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 <td>rpm -ql package_name</td> 
 <td>show list of files provided by a rpm package installed</td> 
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 <td>rpm -qc package_name</td> 
 <td>show list of configuration files provided by a rpm package installed</td> 
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 <td>rpm -q package_name --whatrequires</td> 
 <td>show list of dependencies required for a rpm packet</td> 
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 <td>rpm -q package_name --whatprovides</td> 
 <td>show capability provided by a rpm package</td> 
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 <td>rpm -q package_name --scripts</td> 
 <td>show scripts started during installation / removal</td> 
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 <td>rpm -q package_name --changelog</td> 
 <td>show history of revisions of a rpm package</td> 
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 <td>rpm -qf /etc/httpd/conf/httpd.conf</td> 
 <td>verify which rpm package belongs to a given file</td> 
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 <td>rpm -qp package.rpm&nbsp; -l</td> 
 <td>show list of files provided by a rpm package not yet installed</td> 
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 <td>rpm --import /media/cdrom/RPM-GPG-KEY</td> 
 <td>import public-key digital signature</td> 
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 <td>rpm --checksig package.rpm</td> 
 <td>verify the integrity of a rpm package</td> 
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 <td>rpm -qa gpg-pubkey</td> 
 <td>verify integrity of all rpm packages installed</td> 
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 <td>rpm -V package_name</td> 
 <td>check file size, permissions, type, owner, group, MD5 checksum and last modification</td> 
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 <td>rpm -Va</td> 
 <td>check all rpm packages installed on the system - use with caution</td> 
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 <td>rpm -Vp package.rpm</td> 
 <td>verify a rpm package not yet installed</td> 
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 <td>rpm2cpio package.rpm | cpio --extract --make-directories&nbsp; *bin*</td> 
 <td>extract executable file from a rpm package</td> 
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 <td>rpm -ivh /usr/src/redhat/RPMS/`arch`/package.rpm</td> 
 <td>install a package built from a rpm source</td> 
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 <td>rpmbuild --rebuild package_name.src.rpm</td> 
 <td>build a rpm package from a rpm source</td> 
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 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
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 <td colspan="2"> YUM packages updater - Fedora, RedHat and like </td> 
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 <td>yum install package_name</td> 
 <td>download and install a rpm package</td> 
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 <td>yum update</td> 
 <td>update all rpm packages installed on the system</td> 
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 <td>yum update package_name</td> 
 <td>upgrade a rpm package</td> 
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 <td>yum remove package_name</td> 
 <td>remove a rpm package</td> 
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 <td>yum list</td> 
 <td>list all packages installed on the system</td> 
 </tr> 
 <tr> 
 <td>yum search package_name</td> 
 <td>find a package on rpm repository</td> 
 </tr> 
 <tr> 
 <td>yum clean packages</td> 
 <td>clean up rpm cache erasing downloaded packages</td> 
 </tr> 
 <tr> 
 <td>yum clean headers</td> 
 <td>remove all files headers that the system uses to resolve dependency</td> 
 </tr> 
 <tr> 
 <td>yum clean all</td> 
 <td>remove from the cache packages and headers files</td> 
 </tr> 
 <tr> 
 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
 </tr> 
 <tr> 
 <td colspan="2"> DEB packages - Debian, Ubuntu and like </td> 
 </tr> 
 <tr> 
 <td>dpkg -i package.deb</td> 
 <td>install / upgrade a deb package</td> 
 </tr> 
 <tr> 
 <td>dpkg -r package_name</td> 
 <td>remove a deb package from the system</td> 
 </tr> 
 <tr> 
 <td>dpkg -l</td> 
 <td>show all deb packages installed on the system</td> 
 </tr> 
 <tr> 
 <td>dpkg -l | grep httpd</td> 
 <td>show all rpm packages with the name "httpd"</td> 
 </tr> 
 <tr> 
 <td>dpkg -s package_name</td> 
 <td>obtain information on a specific package installed on system</td> 
 </tr> 
 <tr> 
 <td>dpkg -L package_name</td> 
 <td>show list of files provided by a package installed on system</td> 
 </tr> 
 <tr> 
 <td>dpkg --contents package.deb</td> 
 <td>show list of files provided by a package not yet installed</td> 
 </tr> 
 <tr> 
 <td>dpkg -S /bin/ping</td> 
 <td>verify which package belongs to a given file</td> 
 </tr> 
 <tr> 
 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
 </tr> 
 <tr> 
 <td colspan="2"> APT packages updater - Debian, Ubuntu e like </td> 
 </tr> 
 <tr> 
 <td>apt-get install package_name</td> 
 <td>install / upgrade a deb package</td> 
 </tr> 
 <tr> 
 <td>apt-cdrom install package_name</td> 
 <td>install / upgrade a deb package from cdrom</td> 
 </tr> 
 <tr> 
 <td>apt-get update</td> 
 <td>update all deb packages installed on system</td> 
 </tr> 
 <tr> 
 <td>apt-get remove package_name</td> 
 <td>remove a deb package from system</td> 
 </tr> 
 <tr> 
 <td>apt-get check</td> 
 <td>verify correct resolution of dependencies</td> 
 </tr> 
 <tr> 
 <td>apt-get clean</td> 
 <td>clean up cache from packages downloaded</td> 
 </tr> 
 <tr> 
 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
 </tr> 
 <tr> 
 <td colspan="2"> View file content </td> 
 </tr> 
 <tr> 
 <td>cat file1</td> 
 <td>view the contents of a file starting from the first row</td> 
 </tr> 
 <tr> 
 <td>tac file1</td> 
 <td>view the contents of a file starting from the last line</td> 
 </tr> 
 <tr> 
 <td>more file1</td> 
 <td>view content of a file along</td> 
 </tr> 
 <tr> 
 <td>less file1</td> 
 <td>similar to 'more' command but which allows backward movement in the file as well as forward movement</td> 
 </tr> 
 <tr> 
 <td>head -2 file1</td> 
 <td>view first two lines of a file</td> 
 </tr> 
 <tr> 
 <td>tail -2 file1</td> 
 <td>view last two lines of a file</td> 
 </tr> 
 <tr> 
 <td>tail -f /var/log/messages</td> 
 <td>view in real time what is added to a file</td> 
 </tr> 
 <tr> 
 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
 </tr> 
 <tr> 
 <td colspan="2"> Text Manipulation </td> 
 </tr> 
 <tr> 
 <td>cat file_test | [operation: sed, grep, awk, grep, etc] &gt; result.txt</td> 
 <td>syntax to elaborate the text of a file, and write result to a new file</td> 
 </tr> 
 <tr> 
 <td>cat file_originale | [operazione: sed, grep, awk, grep, etc] &gt;&gt; result.txt</td> 
 <td>syntax to elaborate the text of a file and append result in existing file</td> 
 </tr> 
 <tr> 
 <td>grep Aug /var/log/messages</td> 
 <td>look up words "Aug" on file '/var/log/messages'</td> 
 </tr> 
 <tr> 
 <td>grep ^Aug /var/log/messages</td> 
 <td>look up words that begin with "Aug" on file '/var/log/messages'</td> 
 </tr> 
 <tr> 
 <td>grep [0-9] /var/log/messages</td> 
 <td>select from file '/var/log/messages' all lines that contain numbers</td> 
 </tr> 
 <tr> 
 <td>grep Aug -R /var/log/*</td> 
 <td>search string "Aug" at directory '/var/log' and below</td> 
 </tr> 
 <tr> 
 <td>grep Aug /var/log/messages</td> 
 <td>write result of a search within a file</td> 
 </tr> 
 <tr> 
 <td>sed 's/stringa1/stringa2/g' example.txt</td> 
 <td>replace "string1" with "string2" in example.txt</td> 
 </tr> 
 <tr> 
 <td>sed '/^$/d' example.txt</td> 
 <td>remove all blank lines from example.txt</td> 
 </tr> 
 <tr> 
 <td>sed '/ *#/d; /^ *$/d' example.txt</td> 
 <td>remove comments and blank lines from example.txt</td> 
 </tr> 
 <tr> 
 <td>echo 'esempio' | tr '[:lower:]' '[:upper:]'</td> 
 <td>convert from lower case in upper case</td> 
 </tr> 
 <tr> 
 <td>sed -e '1d' result.txt</td> 
 <td>eliminates the first line from file example.txt</td> 
 </tr> 
 <tr> 
 <td>sed -n '/stringa1/p'</td> 
 <td>view only lines that contain the word "string1"</td> 
 </tr> 
 <tr> 
 <td>sed -e 's/ *$//' example.txt</td> 
 <td>remove empty characters at the end of each row</td> 
 </tr> 
 <tr> 
 <td>sed -e 's/stringa1//g' example.txt</td> 
 <td>remove only the word "string1" from text and leave intact all</td> 
 </tr> 
 <tr> 
 <td>sed -n '1,5p;5q' example.txt</td> 
 <td>view from 1th to 5th row</td> 
 </tr> 
 <tr> 
 <td>sed -n '5p;5q' example.txt</td> 
 <td>view row number 5</td> 
 </tr> 
 <tr> 
 <td>sed -e 's/00*/0/g' example.txt</td> 
 <td>replace more zeros with a single zero</td> 
 </tr> 
 <tr> 
 <td>cat -n file1</td> 
 <td>number row of a file</td> 
 </tr> 
 <tr> 
 <td>cat example.txt | awk 'NR%2==1'</td> 
 <td>remove all even lines from example.txt</td> 
 </tr> 
 <tr> 
 <td>echo a b c | awk '{print $1}'</td> 
 <td>view the first column of a line</td> 
 </tr> 
 <tr> 
 <td>echo a b c | awk '{print $1,$3}'</td> 
 <td>view the first and third column of a line</td> 
 </tr> 
 <tr> 
 <td>paste file1 file2</td> 
 <td>merging contents of two files for columns</td> 
 </tr> 
 <tr> 
 <td>paste&nbsp; -d&nbsp; '+' file1 file2</td> 
 <td>merging contents of two files for columns with '+' delimiter on the center</td> 
 </tr> 
 <tr> 
 <td>sort file1 file2</td> 
 <td>sort contents of two files</td> 
 </tr> 
 <tr> 
 <td>sort file1 file2 | uniq</td> 
 <td>sort contents of two files omitting lines repeated</td> 
 </tr> 
 <tr> 
 <td>sort file1 file2 | uniq -u</td> 
 <td>sort contents of two files by viewing only unique line</td> 
 </tr> 
 <tr> 
 <td>sort file1 file2 | uniq -d</td> 
 <td>sort contents of two files by viewing only duplicate line</td> 
 </tr> 
 <tr> 
 <td>comm -1 file1 file2</td> 
 <td>compare contents of two files by deleting only unique lines from 'file1'</td> 
 </tr> 
 <tr> 
 <td>comm -2 file1 file2</td> 
 <td>compare contents of two files by deleting only unique lines from 'file2'</td> 
 </tr> 
 <tr> 
 <td>comm -3 file1 file2</td> 
 <td>compare contents of two files by deleting only the lines that appear on both files</td> 
 </tr> 
 <tr> 
 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
 </tr> 
 <tr> 
 <td colspan="2">Character set and Format file conversion </td> 
 </tr> 
 <tr> 
 <td>dos2unix filedos.txt fileunix.txt</td> 
 <td>convert a text file format from MSDOS to UNIX</td> 
 </tr> 
 <tr> 
 <td>unix2dos fileunix.txt filedos.txt</td> 
 <td>convert a text file format from UNIX to MSDOS</td> 
 </tr> 
 <tr> 
 <td>recode ..HTML &lt; page.txt &gt; page.html</td> 
 <td>convert a text file to html</td> 
 </tr> 
 <tr> 
 <td>recode -l | more</td> 
 <td>show all available formats conversion</td> 
 </tr> 
 <tr> 
 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
 </tr> 
 <tr> 
 <td colspan="2"> Filesystem Analysis </td> 
 </tr> 
 <tr> 
 <td>badblocks&nbsp; -v&nbsp; /dev/hda1</td> 
 <td>check bad blocks in disk hda1</td> 
 </tr> 
 <tr> 
 <td>fsck&nbsp; /dev/hda1</td> 
 <td>repair / check integrity of linux filesystem on disk hda1</td> 
 </tr> 
 <tr> 
 <td>fsck.ext2&nbsp; /dev/hda1</td> 
 <td>repair / check integrity of ext2 filesystem on disk hda1</td> 
 </tr> 
 <tr> 
 <td>e2fsck&nbsp; /dev/hda1</td> 
 <td>repair / check integrity of ext2 filesystem on disk hda1</td> 
 </tr> 
 <tr> 
 <td>e2fsck -j /dev/hda1</td> 
 <td>repair / check integrity of ext3 filesystem on disk hda1</td> 
 </tr> 
 <tr> 
 <td>fsck.ext3&nbsp; /dev/hda1</td> 
 <td>repair / check integrity of ext3 filesystem on disk hda1</td> 
 </tr> 
 <tr> 
 <td>fsck.vfat&nbsp; /dev/hda1</td> 
 <td>repair / check integrity of fat filesystem on disk hda1</td> 
 </tr> 
 <tr> 
 <td>fsck.msdos&nbsp; /dev/hda1</td> 
 <td>repair / check integrity of dos filesystem on disk hda1</td> 
 </tr> 
 <tr> 
 <td>dosfsck&nbsp; /dev/hda1</td> 
 <td>repair / check integrity of dos filesystems on disk hda1</td> 
 </tr> 
 <tr> 
 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
 </tr> 
 <tr> 
 <td colspan="2"> Format a Filesystem </td> 
 </tr> 
 <tr> 
 <td>mkfs /dev/hda1</td> 
 <td>create a filesystem type linux on hda1 partition</td> 
 </tr> 
 <tr> 
 <td>mke2fs /dev/hda1</td> 
 <td>create a filesystem type linux ext2 on hda1 partition</td> 
 </tr> 
 <tr> 
 <td>mke2fs -j /dev/hda1</td> 
 <td>create a filesystem type linux ext3 (journal) on hda1 partition</td> 
 </tr> 
 <tr> 
 <td>mkfs -t vfat 32 -F /dev/hda1</td> 
 <td>create a FAT32 filesystem</td> 
 </tr> 
 <tr> 
 <td>fdformat&nbsp; -n /dev/fd0</td> 
 <td>format a floppy disk</td> 
 </tr> 
 <tr> 
 <td>mkswap /dev/hda3</td> 
 <td>create a swap filesystem</td> 
 </tr> 
 <tr> 
 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
 </tr> 
 <tr> 
 <td colspan="2"> SWAP filesystem </td> 
 </tr> 
 <tr> 
 <td>mkswap /dev/hda3</td> 
 <td>create a swap filesystem</td> 
 </tr> 
 <tr> 
 <td>swapon /dev/hda3</td> 
 <td>activating a new swap partition</td> 
 </tr> 
 <tr> 
 <td>swapon /dev/hda2 /dev/hdb3&nbsp;</td> 
 <td>activate two swap partitions</td> 
 </tr> 
 <tr> 
 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
 </tr> 
 <tr> 
 <td colspan="2"> Backup </td> 
 </tr> 
 <tr> 
 <td>dump -0aj -f /tmp/home0.bak /home&nbsp;</td> 
 <td>make a full backup of directory '/home'</td> 
 </tr> 
 <tr> 
 <td>dump -1aj -f /tmp/home0.bak /home&nbsp;</td> 
 <td>make a incremental backup of directory '/home'</td> 
 </tr> 
 <tr> 
 <td>restore -if /tmp/home0.bak</td> 
 <td>restoring a backup interactively</td> 
 </tr> 
 <tr> 
 <td>rsync -rogpav --delete /home /tmp</td> 
 <td>synchronization between directories</td> 
 </tr> 
 <tr> 
 <td>rsync -rogpav -e ssh --delete /home ip_address:/tmp&nbsp;</td> 
 <td>rsync via SSH tunnel</td> 
 </tr> 
 <tr> 
 <td>rsync -az -e ssh --delete ip_addr:/home/public /home/local</td> 
 <td>synchronize a local directory with a remote directory via ssh and compression</td> 
 </tr> 
 <tr> 
 <td>rsync -az -e ssh --delete /home/local ip_addr:/home/public</td> 
 <td>synchronize a remote directory with a local directory via ssh and compression</td> 
 </tr> 
 <tr> 
 <td>dd bs=1M if=/dev/hda | gzip | ssh user@ip_addr 'dd of=hda.gz'</td> 
 <td>make a backup of a local hard disk on remote host via ssh</td> 
 </tr> 
 <tr> 
 <td>tar -Puf backup.tar /home/user</td> 
 <td>make a incremental backup of directory '/home/user'</td> 
 </tr> 
 <tr> 
 <td>( cd /tmp/local/ &amp;&amp; tar c . ) | ssh -C user@ip_addr 'cd /home/share/ &amp;&amp; tar x -p'</td> 
 <td>copy content of a directory on remote directory via ssh</td> 
 </tr> 
 <tr> 
 <td>( tar c /home ) | ssh -C user@ip_addr 'cd /home/backup-home &amp;&amp; tar x -p'&nbsp;</td> 
 <td>copy a local directory on remote directory via ssh</td> 
 </tr> 
 <tr> 
 <td>tar cf - . | (cd /tmp/backup ; tar xf - )</td> 
 <td>local copy preserving permits and links from a directory to another</td> 
 </tr> 
 <tr> 
 <td>find /home/user1 -name '*.txt' | xargs cp -av --target-directory=/home/backup/ --parents</td> 
 <td>find and copy all files with '.txt' extention from a directory to another</td> 
 </tr> 
 <tr> 
 <td>find /var/log -name '*.log' | tar cv --files-from=- | bzip2 &gt; log.tar.bz2</td> 
 <td>find all files with '.log' extention and make an bzip archive</td> 
 </tr> 
 <tr> 
 <td>dd if=/dev/hda of=/dev/fd0 bs=512 count=1</td> 
 <td>make a copy of MBR (Master Boot Record) to floppy</td> 
 </tr> 
 <tr> 
 <td>dd if=/dev/fd0 of=/dev/hda bs=512 count=1</td> 
 <td>restore MBR from backup copy saved to floppy</td> 
 </tr> 
 <tr> 
 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
 </tr> 
 <tr> 
 <td colspan="2"> CDROM </td> 
 </tr> 
 <tr> 
 <td>cdrecord -v gracetime=2 dev=/dev/cdrom -eject blank=fast -force</td> 
 <td>clean a rewritable cdrom</td> 
 </tr> 
 <tr> 
 <td>mkisofs /dev/cdrom &gt; cd.iso</td> 
 <td>create an iso image of cdrom on disk</td> 
 </tr> 
 <tr> 
 <td>mkisofs /dev/cdrom | gzip &gt; cd_iso.gz</td> 
 <td>create a compressed iso image of cdrom on disk</td> 
 </tr> 
 <tr> 
 <td>mkisofs -J -allow-leading-dots -R -V "Label CD" -iso-level 4 -o ./cd.iso data_cd</td> 
 <td>create an iso image of a directory</td> 
 </tr> 
 <tr> 
 <td>cdrecord -v dev=/dev/cdrom cd.iso</td> 
 <td>burn an ISO image</td> 
 </tr> 
 <tr> 
 <td>gzip -dc cd_iso.gz | cdrecord dev=/dev/cdrom -</td> 
 <td>burn a compressed ISO image</td> 
 </tr> 
 <tr> 
 <td>mount -o loop cd.iso /mnt/iso</td> 
 <td>mount an ISO image</td> 
 </tr> 
 <tr> 
 <td>cd-paranoia -B</td> 
 <td>rip audio tracks from a CD to wav files</td> 
 </tr> 
 <tr> 
 <td>cd-paranoia -- "-3"</td> 
 <td>rip first three audio tracks from a CD to wav files</td> 
 </tr> 
 <tr> 
 <td>cdrecord --scanbus</td> 
 <td>scan bus to identify the channel scsi</td> 
 </tr> 
 <tr> 
 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
 </tr> 
 <tr> 
 <td colspan="2"> Networking - LAN and WiFi </td> 
 </tr> 
 <tr> 
 <td>ifconfig eth0</td> 
 <td>show configuration of an ethernet network card</td> 
 </tr> 
 <tr> 
 <td>ifup eth0</td> 
 <td>activate an interface 'eth0'</td> 
 </tr> 
 <tr> 
 <td>ifdown eth0</td> 
 <td>disable an interface 'eth0'</td> 
 </tr> 
 <tr> 
 <td>ifconfig eth0 192.168.1.1 netmask 255.255.255.0</td> 
 <td>configure IP Address</td> 
 </tr> 
 <tr> 
 <td>ifconfig eth0 promisc</td> 
 <td>configure 'eth0' in promiscuous mode to gather packets (sniffing)</td> 
 </tr> 
 <tr> 
 <td>dhclient eth0</td> 
 <td>active interface 'eth0' in dhcp mode</td> 
 </tr> 
 <tr> 
 <td>route -n</td> 
 <td>show routing table</td> 
 </tr> 
 <tr> 
 <td>route add -net 0/0 gw IP_Gateway</td> 
 <td>configura default gateway</td> 
 </tr> 
 <tr> 
 <td>route add -net 192.168.0.0 netmask 255.255.0.0 gw 192.168.1.1</td> 
 <td>configure static route to reach network '192.168.0.0/16'</td> 
 </tr> 
 <tr> 
 <td>route del 0/0 gw IP_gateway</td> 
 <td>remove static route</td> 
 </tr> 
 <tr> 
 <td>echo "1" &gt; /proc/sys/net/ipv4/ip_forward</td> 
 <td>activate ip routing</td> 
 </tr> 
 <tr> 
 <td>hostname</td> 
 <td>show hostname</td> 
 </tr> 
 <tr> 
 <td>host www.linuxguide.it</td> 
 <td>lookup hostname to resolve name to ip address and viceversa</td> 
 </tr> 
 <tr> 
 <td>ip link show</td> 
 <td>show link status of all interfaces</td> 
 </tr> 
 <tr> 
 <td>mii-tool eth0</td> 
 <td>show link status of 'eth0'</td> 
 </tr> 
 <tr> 
 <td>ethtool eth0</td> 
 <td>show statistics of network card 'eth0'</td> 
 </tr> 
 <tr> 
 <td>netstat -tup</td> 
 <td>show all active network connections and their PID</td> 
 </tr> 
 <tr> 
 <td>netstat -tupl</td> 
 <td>show all network services listening on the system and their PID</td> 
 </tr> 
 <tr> 
 <td>tcpdump tcp port 80</td> 
 <td>show all HTTP traffic</td> 
 </tr> 
 <tr> 
 <td>iwlist scan</td> 
 <td>show wireless networks</td> 
 </tr> 
 <tr> 
 <td>iwconfig eth1</td> 
 <td>show configuration of a wireless network card</td> 
 </tr> 
 <tr> 
 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
 </tr> 
 <tr> 
 <td colspan="2"> Microsoft Windows networks - SAMBA </td> 
 </tr> 
 <tr> 
 <td>nbtscan ip_addr</td> 
 <td>netbios name resolution</td> 
 </tr> 
 <tr> 
 <td>nmblookup -A ip_addr</td> 
 <td>netbios name resolution</td> 
 </tr> 
 <tr> 
 <td>smbclient -L ip_addr/hostname</td> 
 <td>show remote shares of a windows host</td> 
 </tr> 
 <tr> 
 <td>smbget -Rr smb://ip_addr/share</td> 
 <td>like wget can download files from a host windows via smb</td> 
 </tr> 
 <tr> 
 <td>mount -t smbfs -o username=user,password=pass //winclient/share /mnt/share</td> 
 <td>mount a windows network share</td> 
 </tr> 
 <tr> 
 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
 </tr> 
 <tr> 
 <td colspan="2"> IPTABLES - firewall </td> 
 </tr> 
 <tr> 
 <td>iptables -t filter -L</td> 
 <td>show all chains of filtering table</td> 
 </tr> 
 <tr> 
 <td>iptables -t nat -L</td> 
 <td>show all chains of nat table</td> 
 </tr> 
 <tr> 
 <td>iptables -t filter -F</td> 
 <td>clear all rules from filtering table</td> 
 </tr> 
 <tr> 
 <td>iptables -t nat -F</td> 
 <td>clear all rules from table nat</td> 
 </tr> 
 <tr> 
 <td>iptables -t filter -X</td> 
 <td>delete any chains created by user</td> 
 </tr> 
 <tr> 
 <td>iptables -t filter -A INPUT -p tcp --dport telnet -j ACCEPT</td> 
 <td>allow telnet connections to input</td> 
 </tr> 
 <tr> 
 <td>iptables -t filter -A OUTPUT -p tcp --dport http -j DROP</td> 
 <td>block HTTP connections to output</td> 
 </tr> 
 <tr> 
 <td>iptables -t filter -A FORWARD -p tcp --dport pop3 -j ACCEPT</td> 
 <td>allow POP3 connections to forward chain</td> 
 </tr> 
 <tr> 
 <td>iptables -t filter -A INPUT -j LOG --log-prefix "DROP INPUT"</td> 
 <td>logging sulla chain di input&nbsp; Logging on chain input</td> 
 </tr> 
 <tr> 
 <td>iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE</td> 
 <td>configure a PAT (Port Address Traslation) on eth0 masking outbound packets</td> 
 </tr> 
 <tr> 
 <td>iptables -t nat -A PREROUTING -d 192.168.0.1 -p tcp -m tcp --dport 22 -j DNAT --to-destination 10.0.0.2:22</td> 
 <td>redirect packets addressed to a host to another host</td> 
 </tr> 
 <tr> 
 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
 </tr> 
 <tr> 
 <td colspan="2"> Monitoring and debugging </td> 
 </tr> 
 <tr> 
 <td>top</td> 
 <td>display linux tasks using most cpu</td> 
 </tr> 
 <tr> 
 <td>ps -eafw</td> 
 <td>displays linux tasks</td> 
 </tr> 
 <tr> 
 <td>ps -e -o pid,args --forest</td> 
 <td>displays linux tasks in a hierarchical mode</td> 
 </tr> 
 <tr> 
 <td>pstree&nbsp;</td> 
 <td>mostra un albero dei processi sistema Shows a tree system processes</td> 
 </tr> 
 <tr> 
 <td>kill -9 ID_Processo</td> 
 <td>force closure of the process and finish it</td> 
 </tr> 
 <tr> 
 <td>kill -1 ID_Processo</td> 
 <td>force a process to reload configuration</td> 
 </tr> 
 <tr> 
 <td>lsof -p $$</td> 
 <td>display a list of files opened by processes</td> 
 </tr> 
 <tr> 
 <td>lsof /home/user1</td> 
 <td>displays a list of open files in a given path system</td> 
 </tr> 
 <tr> 
 <td>strace -c ls &gt;/dev/null</td> 
 <td>display system calls made and received by a process</td> 
 </tr> 
 <tr> 
 <td>strace -f -e open ls &gt;/dev/null</td> 
 <td>display library calls</td> 
 </tr> 
 <tr> 
 <td>watch -n1 'cat /proc/interrupts'</td> 
 <td>display interrupts in real-time</td> 
 </tr> 
 <tr> 
 <td>last reboot</td> 
 <td>show history reboot</td> 
 </tr> 
 <tr> 
 <td>lsmod</td> 
 <td>display kernel loaded</td> 
 </tr> 
 <tr> 
 <td>free -m</td> 
 <td>displays status of RAM in megabytes</td> 
 </tr> 
 <tr> 
 <td>smartctl -A /dev/hda</td> 
 <td>monitoring reliability of a hard-disk through SMART</td> 
 </tr> 
 <tr> 
 <td>smartctl -i /dev/hda</td> 
 <td>check if SMART is active on a hard-disk</td> 
 </tr> 
 <tr> 
 <td>tail /var/log/dmesg</td> 
 <td>show events inherent to the process of booting kernel</td> 
 </tr> 
 <tr> 
 <td>tail /var/log/messages</td> 
 <td>show system events</td> 
 </tr> 
 <tr> 
 <td align="center" colspan="2">linux commands line v1.0 - LinuxGuide.it </td> 
 </tr> 
 <tr> 
 <td colspan="2"> Other useful commands </td> 
 </tr> 
 <tr> 
 <td>mkbootdisk --device /dev/fd0 `uname -r`</td> 
 <td>create a boot floppy</td> 
 </tr> 
 <tr> 
 <td>gpg -c file1</td> 
 <td>encrypt a file with GNU Privacy Guard</td> 
 </tr> 
 <tr> 
 <td>gpg file1.gpg</td> 
 <td>decrypt a file with GNU Privacy Guard</td> 
 </tr> 
 <tr> 
 <td>wget -r www.example.com</td> 
 <td>download an entire web site</td> 
 </tr> 
 <tr> 
 <td>wget -c www.example.com/file.iso</td> 
 <td>download a file with the ability to stop the download and resume later</td> 
 </tr> 
 <tr> 
 <td>echo 'wget -c www.example.com/files.iso' | at 09:00</td> 
 <td>start a download at any given time</td> 
 </tr> 
 <tr> 
 <td>ldd ssh </td> 
 <td>show shared libraries required by ssh program</td> 
 </tr> 
 <tr> 
 <td>alias hh='history'</td> 
 <td>set an alias for a command - hh = history</td> 
 </tr> 
 </tbody> 
 </table> </td> 
 </tr> 
 </tbody> 
</table>