When you perform an upgrade of your Ghost installation, you might run into a little issue towards the end of the upgrade process, specifically when you run this command:

npm install --production

This step might end abruptly with no explanation whatsoever on what is going on. On my machine, this is what happened:

root@hostname:/var/www/ghost# npm install --production
extract → gunzTarPerm ▌ ╢██████████████████████████████████░░░░░░░░░░░░░░░╟
Killed
root@hostname:/var/www/ghost# npm install --production
cloneCurrentTree → attemp ▀ ╢████████░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░╟
Killed

As you can see, even attempting to run the command again didn’t help. After a little bit of digging around, I found out that this is a RAM issue.

The solution

This happens because your system is running out of available RAM to complete this step of the upgrade. You can check your current RAM usage with this command:

free -m

If you encountered this issue, it is very likely you are very close to maxing out your RAM. If this is the case, you have two options to solve this:

  • You can either increase the RAM on this machine (if you are running Ghost in a VM, that will be extremely simple)
  • You can create a swap file on your machine

In my case, I am running Ghost on a DigitalOcean droplet with only 512 MB of RAM, so I decided to go with option number 2. Here is a great guide on how to configure swap space on Linux running in a DigitalOcean Droplet, there is nothing I can add to the article as it’s already excellent as it it.

FYI, the instructions worked on Ubuntu 16.04 too, and to solve this specific issue, creating a swap file of just 512 MB was enough, so there is no need for you to create a bigger one.