Updated readme

README.md

@@ -5,7 +5,7 @@ Webcron management is an easy-to-use interface to manage cronjob running on a pu
 
 ## Requirements
 * Webserver able to run PHP
-* PHP 7.0 or greater
+* PHP 5.6 or greater
 * MySQL/MariaDB
 * Ability to add a system cronjob for installation (You can maybe ask you webhost?)
 
@@ -15,13 +15,27 @@ Follow the instructions below to install the webcron interface
 1. Copy this repository to a public directory on your server
 2. Create a database using the database.sql provided in the repository
 3. Create a first user by inserting a first record to the users table (Password is hashed with bcrypt)
-4. Run composer install to install dependencies.
+4. Run `composer install` to install dependencies.
 5. Open ssh and add following line to your crontab
 
 ```
 * * * * cd /path/to/webcron/ && php webcron.php > /dev/null 1&>2
 ```
 
+## Common pittfalls
+### Cronjobs are not running
+Did you edit the crontab?
+
+### I can't do an automatic system upgrade!
+Doing a system upgrade requires sudo which has a certain number security measurements. To enable running anything with sudo (eg. `sudo apt dist-upgrade -y`) the user needs to be able to run sudo without tty and password.
+
+TL;DR
+* [disable sudo passwords](http://jeromejaglale.com/doc/unix/ubuntu_sudo_without_password) 
+* [disable tty requirement](https://serverfault.com/questions/111064/sudoers-how-to-disable-requiretty-per-user)
+
+### Can I schedule a reboot every week?
+Yes, you can do this by creating a job with `reboot` as "url". When this job needs to run, the reboot is triggered to run at the very end. At the first run of the master script a list of active and terribly failed services is pushed to the job so you can check this if something is wrong.
+
 ## Licence
 
     Permission is hereby granted, free of charge, to any person obtaining a copy