{"id":660,"date":"2021-07-23T12:35:00","date_gmt":"2021-07-23T12:35:00","guid":{"rendered":"https:\/\/ssdsunucum.com\/blog\/getting-started-with-linux-commands\/"},"modified":"2021-07-23T12:35:00","modified_gmt":"2021-07-23T12:35:00","slug":"getting-started-with-linux-commands","status":"publish","type":"post","link":"https:\/\/ssdsunucum.com\/blog\/getting-started-with-linux-commands\/","title":{"rendered":"Getting Started with Linux Commands"},"content":{"rendered":"<\/p>\n
\n
<\/div>\n
\n

Overview<\/h2>\n

While cPanel & WHM automates many server administration tasks, familiarity with the Linux\u00ae command line interface (CLI) can prove useful for both WHM and cPanel users. This documentation gives a brief overview of some basic Linux commands that you may wish to use as you manage your website or server.<\/p>\n

\n
Note:<\/div>\n
\n

For steps to access the command line, read our How to Access the Command Line documentation.<\/p>\n<\/p><\/div>\n<\/div>\n

Common Linux commands<\/h2>\n
\n
Note:<\/div>\n
\n
    \n
  • To execute a command, enter the command with any required options and press Enter<\/kbd>.<\/li>\n
  • In the following examples, replace FILENAME<\/code> with the relative path to the file.<\/li>\n<\/ul><\/div>\n<\/div>\n

    The following lists some basic Linux commands and their functions:<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
    \n
    Command<\/div>\n<\/th>\n
    		Description<\/th>\nExample<\/th>\n<\/tr>\n<\/thead>\n
    cat FILENAME<\/code><\/td>\nPrint the contents of the specified file to the CLI.<\/td>\n\n
    \n
    cat filename.txt<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    cat \/dev\/vcs1<\/code><\/td>\nView the data that currently displays on your server\u2019s console screen.<\/td>\n\n
    \n
    cat \/dev\/vcs1<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    cd LOCATION<\/code><\/td>\nNavigate between directories. Replace LOCATION<\/code> with the path to the directory that you wish to navigate to.<\/td>\n\n
    \n
    cd \/usr\/local\/apache\/<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    chmod permissions FILENAME<\/code><\/td>\nChange a file\u2019s octal permissions. For more information, read Wikipedia\u2019s chmod<\/code> command article.<\/td>\n\n
    \n
    chmod 755<\/span> myfile.txt<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    chown USER:GROUP FILENAME<\/code><\/td>\nChange a file\u2019s user and group ownership. Replace USER<\/code> with the user to whom you wish to grant ownership of the file, GROUP<\/code> with the group name, and FILENAME<\/code> with the relative path to the file.<\/td>\n\n
    \n
    chown user:usersgroup usersfile.txt<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    cp FILE1 FILE2<\/code><\/td>\nCopy a file (FILE1<\/code>) into a new file (FILE2<\/code>).<\/td>\n\n
    \n
    cp original.txt \/copies\/duplicate.txt<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    du<\/code><\/td>\nShow the system\u2019s current disk usage for each directory and subdirectory.<\/td>\n\n
    \n
    du<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    file FILENAME<\/code><\/td>\nGuess a file\u2019s type, based on the file\u2019s contents.<\/td>\n\n
    \n
    file filename<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    grep string FILENAME<\/code><\/td>\nSearch for a string in a specified file and print each line that contains a match to the CLI. Replace string<\/code> with a single word, or multiple words within single quotes (''<\/code>).<\/td>\n\n
    \n
    grep 'thisis anexample'<\/span> filename.txt<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    last<\/code><\/td>\nList which users recently logged in and the timestamp for each login.<\/td>\n\n
    \n
    last<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    ln -s file1 file2<\/code><\/td>\nCreate a symbolic link between the two specified files. Replace file1<\/code> with the relative path to the existing file, and file2<\/code> with the relative path to the new symbolic link file.<\/td>\n\n
    \n
    ln -s \/pointtome\/file1.txt symlink-file2.txt<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    ls<\/code><\/td>\nList files and directories that exist within your current directory. This command resembles the dir<\/code> command in Windows\u00ae.<\/td>\n\n
    \n
    ls<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    ls -al<\/code><\/td>\nView dotfiles (filenames that begin with a period) and additional file and directory details.<\/td>\n\n
    \n
    ls -al<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    more FILENAME<\/code><\/td>\nPrint the contents of a file to the CLI, one screen at a time.<\/td>\n\n
    \n
    more filename.txt<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    netstat<\/code><\/td>\nList all of the server\u2019s current network connections.<\/td>\n\n
    \n
    netstat<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    pico FILENAME<\/code><\/td>\nOpen the specified file in the pico text editor.<\/td>\n\n
    \n
    pico filename.txt<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    ps<\/code><\/td>\nReturn information about the server\u2019s current processes. <\/p>\n
    \n
    Note:<\/div>\n
    \n To view all of the running processes add the -auxww<\/code> or -cef<\/code> option to this command.\n <\/div>\n<\/div>\n<\/td>\n
    		\n
    \n
    ps<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    rm FILENAME<\/code><\/td>\nDelete the specified file. After you run this command, the system prompts you to confirm the file\u2019s deletion.<\/td>\n\n
    \n
    rm trash.txt<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    tail -## FILENAME<\/code><\/td>\nPrint the last lines of a file to the CLI, where ##<\/code> represents the number of lines to print.<\/td>\n\n
    \n
    tail -20 filename.txt<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    touch FILENAME<\/code><\/td>\nCreate an empty file in the specified location.<\/td>\n\n
    \n
    touch example.txt<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    vi FILENAME<\/code><\/td>\nOpen the specified file in the vi text editor.<\/td>\n\n
    \n
    vi filename.txt<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    w<\/code><\/td>\nList currently logged-in users and the location from which they logged in.<\/td>\n\n
    \n
    w<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    wc FILENAME<\/code><\/td>\nDisplay the word count for a specific file.<\/td>\n\n
    \n
    wc example.txt<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n
    whereis NAME<\/code><\/td>\nQuery applications that match the NAME<\/code> value. You can find the most common applications in the following locations: <\/p>\n
      \n
    • \/usr\/sbin\/sendmail<\/code><\/li>\n
    • \/usr\/bin\/perl<\/code><\/li>\n
    • \/bin\/mail<\/code><\/li>\n
    • \/usr\/bin\/php<\/code><\/li>\n<\/ul>\n<\/td>\n
    		\n
    \n
    whereis perl<\/code><\/pre>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
    Run multiple commands on the same line<\/h3>\n
    Various command-line tasks may require that you use different commands on the same line. Linux includes easy methods to perform these tasks:<\/p>\n
      \n
    • Use the pipe character (|<\/code>) to retrieve data from one program and \u201cpipe\u201d it to another program.<\/li>\n
    • Use a single greater-than bracket (><\/code>) to create a new file if the file does not already exist, or to overwrite any existing content if the file does exist.<\/li>\n
    • Use a double greater-than bracket (>><\/code>) to create a new file if the file does not already exist, or to append the new data to the file if the file does exist.<\/li>\n
    • Use a single less-than bracket (<<\/code>) to send input from a file to a command.<\/li>\n<\/ul>\n
      The following are examples of how to combine tasks into a single command:<\/p>\n\n\n\n\n\n\n\n\n\n
      Command<\/th>\nDescription<\/th>\n<\/tr>\n<\/thead>\n
      \n
      \n
      grep User \/usr\/local\/apache\/conf\/httpd.conf | more<\/code><\/pre>\n<\/div>\n<\/td>\n
      		This command searches for all of the lines in the httpd.conf<\/code> file that match the User<\/code> search term, and then prints the results to your terminal one screen at a time.<\/td>\n<\/tr>\n
      \n
      \n
      last -a > \/root\/lastlogins.tmp<\/code><\/pre>\n<\/div>\n<\/td>\n
      		This command prints all of the current login history to the \/root\/lastlogins.tmp<\/code> file.<\/td>\n<\/tr>\n
      \n
      \n
      mysql --skip-column-names --batch -e 'show processlist'<\/span> | wc -l<\/code><\/pre>\n<\/div>\n<\/td>\n
      		This command lists the number of MySQL\u00ae threads. If subselect expressions start new threads, the output of the show processlist<\/code> command includes them.<\/td>\n<\/tr>\n
      \n
      \n
      netstat -an | grep :80 | wc -l<\/code><\/pre>\n<\/div>\n<\/td>\n
      		This command shows the number of active connections to Apache\u00ae. Apache\u2019s httpd<\/code> daemon runs on port 80<\/code>.<\/td>\n<\/tr>\n
      \n
      \n
      tail -10000 \/var\/log\/exim_mainlog | grep 'example.com'<\/span> | more<\/code><\/pre>\n<\/div>\n<\/td>\n
      		This command finds the last 10,000 lines from the \/var\/log\/exim_mainlog<\/code> file, searches those lines for all occurrences of the string example.com<\/code>, and then prints the search results to your terminal one screen at a time. <\/p>\n
      \n
      Note:<\/div>\n
      \n        The system treats periods (.<\/code>) in a command as wildcard characters. Precede each period with a backslash (<\/code>) to instruct grep to interpret the period literally.\n    <\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
      Common configuration files and directories<\/h2>\n
      You can find common configuration files and directories in the following locations on your server:<\/p>\n\n\n\n\n\n\n\n\n\n
      Service<\/th>\nLocations<\/th>\n<\/tr>\n<\/thead>\n
      Exim<\/td>\n\n
        \n
      • \/etc\/exim.conf<\/code> <\/li>\n
      •  \/var\/log\/exim_mainlog<\/code> <\/li>\n
      •  \/var\/log\/exim_rejectlog<\/code> <\/li>\n
      •  \/etc\/valiases\/<\/code> <\/li>\n
      •  \/etc\/vfilters\/<\/code> <\/li>\n
      •  \/home\/username\/.forward<\/code><\/li>\n<\/ul>\n<\/td>\n<\/tr>\n
      MySQL<\/td>\n\n
        \n
      • \/root\/.my.cnf<\/code> <\/li>\n
      •  \/etc\/my.cnf<\/code> <\/li>\n
      •  \/var\/lib\/mysql\/<\/code><\/li>\n<\/ul>\n<\/td>\n<\/tr>\n
      ProFTPD<\/td>\n\n
        \n
      • \/etc\/proftpd.conf<\/code> <\/li>\n
      •  \/var\/log\/xferlog<\/code> <\/li>\n
      •  \/etc\/proftpd\/<\/code><\/li>\n<\/ul>\n<\/td>\n<\/tr>\n
      SSH<\/td>\n\/etc\/ssh\/sshd_config<\/code><\/td>\n<\/tr>\n
      System<\/td>\n\n
        \n
      • \/var\/log\/messages<\/code> <\/li>\n
      •  \/var\/log\/dmesg<\/code><\/li>\n<\/ul>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table><\/div>\n","protected":false},"excerpt":{"rendered":"
        Overview While cPanel & WHM automates many server administration tasks, familiarity with the Linux\u00ae command line interface (CLI) can prove useful for both WHM and cPanel users. This documentation gives a brief overview of some basic Linux commands that you may wish to use as you manage your website or server. Note: For steps to …<\/p>\n","protected":false},"author":1,"featured_media":661,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/ssdsunucum.com\/blog\/wp-json\/wp\/v2\/posts\/660"}],"collection":[{"href":"https:\/\/ssdsunucum.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ssdsunucum.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ssdsunucum.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ssdsunucum.com\/blog\/wp-json\/wp\/v2\/comments?post=660"}],"version-history":[{"count":0,"href":"https:\/\/ssdsunucum.com\/blog\/wp-json\/wp\/v2\/posts\/660\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/ssdsunucum.com\/blog\/wp-json\/wp\/v2\/media\/661"}],"wp:attachment":[{"href":"https:\/\/ssdsunucum.com\/blog\/wp-json\/wp\/v2\/media?parent=660"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ssdsunucum.com\/blog\/wp-json\/wp\/v2\/categories?post=660"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ssdsunucum.com\/blog\/wp-json\/wp\/v2\/tags?post=660"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}