Magento 2 and PHP load errors

[CursedChico]

what are my errrors

sudo ./magento setup:upgrade
PHP Fatal error:  Uncaught Error: Class 'DOMDocument' not found in /var/www/html/magento/vendor/magento/framework/Config/Dom.php:377
Stack trace:
#0 /var/www/html/magento/vendor/magento/framework/Config/Dom.php(109): Magento\Framework\Config\Dom->_initDom('<?xml version="...')
#1 /var/www/html/magento/vendor/magento/framework/ObjectManager/Config/Reader/Dom.php(70): Magento\Framework\Config\Dom->__construct('<?xml version="...', Object(Magento\Framework\App\Arguments\ValidationState), Array, 'xsi:type', NULL)
#2 /var/www/html/magento/vendor/magento/framework/Config/Reader/Filesystem.php(146): Magento\Framework\ObjectManager\Config\Reader\Dom->_createConfigMerger('Magento\\Framewo...', '<?xml version="...')
#3 /var/www/html/magento/vendor/magento/framework/Config/Reader/Filesystem.php(127): Magento\Framework\Config\Reader\Filesystem->_readFiles(Object(Magento\Framework\Config\FileIterator))
#4 /var/www/html/magento/vendor/magento/framework/App/ObjectManagerFactory.php(282): Magento\Framework\Config\Reader\Filesystem->read('prim in /var/www/html/magento/vendor/magento/framework/Config/Dom.php on line 377

[inrsaurabh]

I facing the same issue. Here is my dom information from phpinfo dom

DOM/XML	enabled
DOM/XML API Version	20031129
libxml Version	2.8.0
HTML Support	enabled
XPath Support	enabled
XPointer Support	enabled
Schema Support	enabled
RelaxNG Support	enabled

[Emizen Tech]

to install IonCube into CentOS, follow these steps : 

login via SSH/Terminal and cd your website home dir 

cd /path/to/www

now wget IonCube loader files 

32-bit : 

wget https://downloads.ioncube.com/loader_downloads/ioncube_loaders_lin_x86.tar.gz

64-bit:

wget https://downloads.ioncube.com/loader_downloads/ioncube_loaders_lin_x86-64.tar.gz

if links are not working than you can get latest links from here

Extract the downloaded file

tar -xzf ioncube_loaders_lin_*.gz

now you need to open loader file in browser by adding 

ioncube/loader-wizard.php to your website 
ex: 

http://magento2store.com/ioncube/loader-wizard.php

now just follow the instructions and it will show you exact .so file which you need to use for your server 

now edit your php.ini file and add this .so file 

zend_extension = /var/www/vhosts/magento2store.com/ioncube/ioncube_loader_lin_5.3.so

now restart Apache

service httpd restart

now you can check if its loaded in same loader file in browser  

[dikey]

I suppose that you need to install all required php extensions.

http://devdocs.magento.com/guides/v2.1/install-gde/system-requirements-tech.html