Here are the steps when you encounter the error below, it means that the yaml library is missing as it is not native to php per say
undefined function yaml_parse_file
Install YAML library for PHP when you see the error below
yum search yaml
First step is to install yaml via pecl
pecl install yaml-2.0.0
Second step is to create the following file
/etc/php/conf.d/ext-yaml.ini
And add the following line
echo "extension=yaml.so"
Then restart php server
service php-fpm restart
