What is the role of Crypt Key in env.php Magento 2

Question

What is the role of crypt in env.php in magento 2. The file is located at app/etc/env.php

Answer 1

During the installation process, Magento 2 will generate a random encryption key, stored in app/etc/env.php. It is used to protect passwords and other sensitive data, using hash & salt method.

For a better understanding, you can take a look in vendor\magento\framework\Encryption\Encryptor.php class which implements EncryptorInterface.

Where is used ? For example in module-customer, module-sales, module-paypal (you can search by EncryptorInterface in vendor/magento to find all the modules that are using it.)

Answer 2

Found this: http://devdocs.magento.com/guides/v2.0/config-guide/config/config-php.html

Look for "Encryption key" on the page

And you might want to look at this: http://devdocs.magento.com/guides/v2.1/cloud/trouble/trouble-crypt-key-variable.html

Apparently the crypt key is Magento generated and used in cloud environments.