As system administrators, we often encounter an array of quirks and challenges. One of the common problems we usually face involves running out of storage space, leading to an error message that says “No space left on device”. This error often occurs when the inode usage on your device exceeds its limit or the filesystem is filled up, leaving you with no space to perform any operations.
What is an Inode?
Before examining the potential solutions we should use, let’s discuss “inodes”. They’re data structures in Unix-style systems that store information about files. Every file uses one inode, so if you have a multitude of small files, you could use up your inodes without filling up your file space.
How to Check Inode Usage
Let’s start by checking inode usage with the following command:
The result should list your current inode usage for each partition. If you see 100% usage on any partition, you’ve identified your problem.
Solving the Issue Using Tar
We can use the Tar command-line utility, which stands for Tape Archiver, to manage inode usage efficiently. Tar is widely used for archiving multiple files into one .tar file or even a .tar.gz file (compressed format). This technique reduces thousands (or even millions) of inodes into one or two, depending on whether we compress the file.
Follow these steps to archive your files:
1. Identify the directory with many small files.
For example, we’ll assume /tmp/files/ is the directory creating inode pollution.
2. Using the Tar utility to convert the directory into a .tar.gz file (compressed file), run:
tar -czvf files.tar.gz /tmp/files/
3. Once the process completes, verify that the tar file exists and has copies of all files with:
tar -tf files.tar.gz
4. If verification is successful, delete the original directory:
rm -r /tmp/files/
Additional Cleanup Steps
If you still have insufficient space, you may also want to consider checking:
- Old and unnecessary log files within /var/log/
- Unused packages and system caches.
- Old kernels that are no longer in use.
Hopefully, these tidbits of information and steps have provided you with useful insights on how to solve the ‘No space left on device’ problem using tar. With proper knowledge and use of resources, you can keep your Debian systems running smoothly!