This tutorial describes how to connect to a remote service via tunnel when only most basic software is available on the remote server. It is not directly related to Yii. It could be hovewer useful for web developers working with shared hosting sites with limited access.
Ok, so you have a HTML 5 file input markup on your view and you have enabled multiple attribute to true. You may also be using widgets based on HTML5 input like \kartik\widgets\FileInput. But when you read a file in Yii controller using CUploadedFile (Yii1) or UploadedFile (Yii2), you do not see a list of multiple files that you selected in your view, but only one row. Your HTML markup in your view would be something like this and you don't know why this is not working?
This Behaviour helps to view time/date/timestamp/datetime from db to local Date / Time / Date Time format and in local Timezone. And save into db in with db timezone and db format. You only need to include this behaviour in models where need this facility.