Ssh

sshd

The sshd daemon will be used to access the system. If we want to have multiple web instances, each one managed by different individuals, we’d usually think about setting up a FTP server and create virtual users (so we know they cannot log in). Or, we can use the SFTP subsystem, rely on the OS user management and also have Secure FTP only access to our system. Even more, we can create RSA keys for the users so they don’t need to worry about passwords. The main features of the setup would be:

• We will grant only SFTP access to the UNIX accounts of the web instances, this way we will have a Secure FTP server that relies on the system accounts. No shell access will be granted to these users.
• The access to the root user is disabled (we can allow forced commands to run rsync scripts)
• The UNIX group sshusers defines the users that can access to a shell via ssh
• The UNIX group sftpweb defines the users that will only access the system via SFTP (they cannot get a shell).This group contains all the users created to run the Web instances. In fact, they will only be able to access a particular directory (in this example this directory is /home/user/data, where the user will find his htdocs/ and logs/ directories of the web instance)
• In the case that Public Key authentication is going to be used, make sure we manage the public keys, so the users cannot modify them.

The idea

I’ve run web servers at home for a quite long time. I used to have my LAMP system (compiled to fit my needs) running on Slackware and it covered all my needs for many years. But during the last years I found myself running very different flavors of Application Servers and I found that my LAMP setup was not flexible enough to deal with such an heterogeneous systems.

I wanted to have a solution that would allow me to run different web servers (apache, nginx, Jetty, flask…), different Application Servers (tomcat, WebLogic, JBoss, Django, perl scripts, etc..) all of them isolated as much as possible from the others.

Since this is a home solution and I cannot afford to have a rack full of blades at home, all these services should run in commodity hardware. I’ve chosen to run it on a laptop, that gives me a UPS service (battery) although it has the drawback of not much CPU power and (most important)  not much RAM. Of course, the solution could be extrapolated to multiple machines, having the ability to grow either horizontally or vertically. But for now, this solution will be confined into a single server 🙁

My ideal solution should, if possible, cover these needs: