If the remote Ubuntu machine does not boot showing the following error

error: unknown filesystem
 Entering rescue mode...
 grub rescue>

the GRUB bootloader is broken and can be fixed in one of the following ways.

Using the GRUB rescue concole

Follow the steps described in this blog post.

Using a …

Here's a collection of links that provide helpful information when you have a brandnew Ubuntu machine with root access and you want to set it up as a webserver:

• https://www.digitalocean.com/community/tutorials/initial-server-setup-with-ubuntu-16-04
• https://www.digitalocean.com/community/tutorials/additional-recommended-steps-for-new-ubuntu-14-04-servers
• https://www.linode.com/docs/security/securing-your-server …

Starting with 15.04, Ubuntu uses systemd instead of Upstart as the default system and service manager. This page offers a good comparison between the two systems.

If you want to add a new systemd service (e.g. for running a Java application everytime your machine boots), create the following …

Assuming you are running an Apache server with a virtual host for abs.mydomain.com, put this into the virtual host's .conf file to redirect all traffic to a Jetty web server running locally behind your Apache:

<Proxy *>
    Order deny,allow
    Allow from all
</Proxy>

ProxyPass / http://localhost:1234/ retry …