How to fix the Filesystem root is running low on Disk space

The Filesystem Root represented by the symbol / is the master directory that holds everything on your virtual server (Ubuntu VM). This is similar to “C: drive” on a Windows machine. In this guide, we shall discuss the steps on how to fix the Filesystem root is running low on Disk space. Please, see Hacker Thinking in Ransomware Attacks: Backup Is the real Target, Bypassing BitLocker Loop by Unlocking or Disabling or PC Reset, and Veeam Host Components: Unable to reinstall Deploy Service SSH.

Every single file, including the Xen Orchestra source code, the database, the logs that fill up your disk earlier, and the operating system itself all live under this root directory.

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Why Low Disk Space on Filesystem root was prompted?

The system notification below explicitly states we have only 337.5MB of disk space remaining. This error occurred from the compiling Xen Orchestra (the xo-server and xo-web build process) which is very resource-heavy. This requires significantly more space than that to store dependencies, build artifacts, and temporary files.

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Temporary Fix

To fix this issues, some of your might want to delete (cleanup) the package cache from updates. This will also not work. Below is the command.

sudo apt-get clean

You might also want to remove old logs from your system has been running a long time. These logs can take up space. But as you know from this guide “A-Z of XCP-ng and Xen Orchestra setup and VM Creation“. This is a pretty new VM and as such, there are no logs that are stale capable of taking space on this system. A you can see, nothing was found and freed.

sudo journalctl --vacuum-time=3d

Now let’s verify if we truly have enough space. To check disk space, please run the command below. As you can see from the available colum, this is less than 1 GB. As such, it will fail when we try to run the Xen Orchestra setup.

df -h /

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Increase File System Size on a VM running on XCP-ng

To fix this permanently, click on the VM to change the Disk size as shown below. We will have to change this from 10GB to 15.

Changed to 15 Gb. This way, we will have more than enough space to install XO.

Note: The above steps are not sufficient to fix this issue as the VM does not correctly know about the disk changes. To demonstrate this, run the XO install again. As you can see below, it will fail again with the below

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Expand the Virtual Disk

Since this is a virtual disk (indicated by the xvda naming convention). As you can see above, we have already increased the disk size which is paramount for this next step. Therefore, run the command below to instruct the VM to use the new space by growing the partition.

sudo growpart /dev/xvda 2

Next, run the command below to resize the filesystem

sudo resize2fs /dev/xvda2

As you can see below from the available disk space, we have 5.2G available. Therefore, we can install XO without issues.

Upon running the command below to install Xen Orchestra (XO) using Ronivay’s script with the command below. Then, select 1 as shown in the image below.