title: LAMP PHP configuration
body: <p><strong>OS: <a href="https://en.wikipedia.org/wiki/Ubuntu_version_history#Ubuntu_17.10_.28Artful_Aardvark.29" rel="nofollow noreferrer">Ubuntu 17.10</a> (Artful Aardvark)</strong> <br/></p>
  <p>I have installed the LAMP stack and Laravel, and when I tried <code>composer install</code> in my Laravel application, I got the following errors.</p>
  <pre class="lang-none prettyprint-override"><code>- Installation request for phar-io/manifest 1.0.1 -&gt; satisfiable by phar-io/manifest[1.0.1].
    - phar-io/manifest 1.0.1 requires ext-dom * -&gt; the requested PHP extension dom is missing from your system.
  Problem 2
    - Installation request for phpunit/php-code-coverage 5.2.2 -&gt; satisfiable by phpunit/php-code-coverage[5.2.2].
    - phpunit/php-code-coverage 5.2.2 requires ext-dom * -&gt; the requested PHP extension dom is missing from your system.
  Problem 3
    - Installation request for phpunit/phpunit 6.4.3 -&gt; satisfiable by phpunit/phpunit[6.4.3].
    - phpunit/phpunit 6.4.3 requires ext-dom * -&gt; the requested PHP extension dom is missing from your system.
  Problem 4
    - Installation request for theseer/tokenizer 1.1.0 -&gt; satisfiable by theseer/tokenizer[1.1.0].
    - theseer/tokenizer 1.1.0 requires ext-dom * -&gt; the requested PHP extension dom is missing from your system.
  
  To enable extensions, verify that they are enabled in your .ini files:
    - /etc/php/7.1/cli/php.ini
    - /etc/php/7.1/cli/conf.d/10-opcache.ini
    - /etc/php/7.1/cli/conf.d/10-pdo.ini
    - /etc/php/7.1/cli/conf.d/20-calendar.ini
    - /etc/php/7.1/cli/conf.d/20-ctype.ini
    - /etc/php/7.1/cli/conf.d/20-exif.ini
    - /etc/php/7.1/cli/conf.d/20-fileinfo.ini
    - /etc/php/7.1/cli/conf.d/20-ftp.ini
    - /etc/php/7.1/cli/conf.d/20-gettext.ini
    - /etc/php/7.1/cli/conf.d/20-iconv.ini
    - /etc/php/7.1/cli/conf.d/20-json.ini
    - /etc/php/7.1/cli/conf.d/20-mbstring.ini
    - /etc/php/7.1/cli/conf.d/20-pdo.ini
    - /etc/php/7.1/cli/conf.d/20-phar.ini
    - /etc/php/7.1/cli/conf.d/20-posix.ini
    - /etc/php/7.1/cli/conf.d/20-readline.ini
    - /etc/php/7.1/cli/conf.d/20-shmop.ini
    - /etc/php/7.1/cli/conf.d/20-sockets.ini
    - /etc/php/7.1/cli/conf.d/20-sysvmsg.ini
    - /etc/php/7.1/cli/conf.d/20-sysvsem.ini
    - /etc/php/7.1/cli/conf.d/20-sysvshm.ini
    - /etc/php/7.1/cli/conf.d/20-tokenizer.ini
  You can also run `php --ini` inside terminal to see which files are used by PHP in CLI mode.
  </code></pre>
  <p>I have rechecked the files, all extensions are enabled and they are located in the
  <code>/usr/lib/php/20160303</code> folder.</p>