Translations:Creating a web server on a cloud/3/en: Difference between revisions

Any time you make a computer accessible to the public, security must be considered. "Accessible to the public" could mean allowing SSH connections, displaying HTML via HTTP, or using 3rd party software to provide a service (e.g. WordPress). Services such as SSH or HTTP are provided by programs called [https://en.wikipedia.org/wiki/Daemon_(computing) "daemons"] which stay running all the time on the computer and respond to outside requests on specific [https://en.wikipedia.org/wiki/Port_(computer_networking) ports]. With [[OpenStack]] you can manage and restrict access to these ports, including granting access only to a specific [https://en.wikipedia.org/wiki/IP_address IP address] or to ranges of IP addresses; see [[OpenStack#Security Groups | Security Groups]]. Restricting access to your VM will improve its security. However, restricting access does not necessarily remove all security vulnerabilities. If we do not use some sort of encryption when sending data (e.g. passwords) an eavesdropper can read that information. [https://en.wikipedia.org/wiki/Transport_Layer_Security Transport Layer Security] is the common way to encrypt this data, and any web site which uses logins (e.g. WordPress, MediaWiki) should use it; see [[Configuring Apache to use SSL]]. It is also possible that data transmitted from your webserver to a client could be modified on route by a third party if you are not encrypting it. While this might not directly cause issues for your webserver it can for your clients. In most cases it is recommended to use encryption on your webserver. You are responsible for the security of your virtual machines and should take it seriously.