In this blog post, we’ll be discussing a critical aspect of Linux file system management – freeing up inodes. An ‘inode’ or ‘index node’ is a data structure that keeps track of all the information about a file, with the exception of its name and actual data.
On some occasions, you might encounter an error message saying ‘No space left on device’ even though there is still plenty of disk space available. In most cases, this means you’ve run out of inodes. This tutorial will guide you on how to free up inodes in Linux.
What Consumes Inodes?
Before we dive into how to free up inodes, let’s understand what consumes them in the first place. Each file and directory on your Linux system uses one inode. Therefore, a large number of small files will consume more inodes than a smaller number of large files.
Checking Inode Usage
Before you start freeing up inodes, you need to check how many are in use and how many are available. You can do this using the df command with the -i option:
df -i
The output will show you the number of inodes used and the percentage of inodes in use for each file system.
Finding Directories with High Inode Usage
Once you know you’re running low on inodes, the next step is to find which directories are using the most. You can use the ncdu tool with the -x and -q options:
ncdu -xq /
This command will perform a disk usage analysis on your root directory and display the directories using the most inodes.
Freeing Up Inodes
Freeing up inodes typically involves deleting unwanted files. For instance, cache folders or logs can often consume a large number of inodes. Before deleting any file or directory, make sure that it isn’t critical to your system or applications.
Preventing Future Inode Exhaustion
Preventing future inode exhaustion requires regular monitoring and maintenance. Keep an eye on your inode usage and delete unnecessary files regularly. Note that creating larger files instead of multiple smaller ones can also help prevent inode exhaustion.
We hope this guide helps you manage your inode usage effectively on your Linux server. As always, exercise caution when deleting files and directories to ensure you don’t remove essential system or application files.
