What Is an Inode?

“Inode” is an important term when it comes to web hosting, and it’s especially important for large website owners and those who host multiple websites via the same hosting company to know what it is. However, most casual users aren’t aware of the existence of inodes unless there is a problem with usage limits.

In this article, we will answer the question “What is an inode?” as well as share tips on how to access your inode information and how to reduce your inode usage.

What Is an Inode & The Origin of the Name

To help you understand what inodes mean in terms of hosting, we first need to explain what the term “inode” means and where it originated from.

In a real-world filing system, there needs to be a record of where each file is. Otherwise, there really wouldn’t be a point in having a filing system. An inode is a concept that solves this problem digitally, in Unix filing systems.

Basically, an inode is a kind of data structure or, a registry, that stores objects on Unix-based filing systems. On Unix-based filing systems, files are stored in two ways. One type of storage, the directory, contains the actual contents of the file, while inodes, the other type of storage, contain information about the file. 

Inodes may contain various types of data such as: 

• File type,
• Size,
• Images and photos,
• Emails,
• Links, 
• Date/time, 
• File directory, 
• Owner of the file, 

and any additional related metadata. However, file names and the file’s content’s data are not stored in inodes.

The inode numbers indicate how many files can be created in a file system. Once the inode number is entered, it can’t be changed. If there’s free space on the disk for a new file but there are no available inode numbers left, the file will not be created. However, the existing files may grow in size. The inode number limit has nothing to do with the size of the files. 

The Origin of the Name

There’s no definitive answer to what the “i” in inode stands for, but it’s widely accepted that it simply refers to “index node”. 

In a paper written by the key developers of the Unix system Dennis Ritchie and Ken Thompson, the term “i-number” is explained as an “index number”. This fact supports many people’s belief that the term actually originated from “index node”.

What Is an Inode in the Context of Hosting?

In the most simple terms, inodes are the number of files a user can have on their hosting account. Each file on the server has a unique inode number. The same is true for any file, no matter how large it is. 

For example, a user with little storage space can use up all of the available inodes included in their plan if they are storing too many files, even if they are very small files. Or similarly, a user may have a few large-size files and think that they need more inodes on their plan, but file size storage limits and inode limits are not to be confused with.

If there were no inode limits on hosting plans, one user could use up a large number of inodes, leaving others on the platform with fewer inodes to work with. Since this wouldn’t be a fair way to provide a service, hosting service providers assign an inode limit for each user. If this limit is reached, your website may be unreachable until you reduce the number of inodes you use on your account.

Even if there weren’t any limitations set by a shared hosting service, because every filing system has to have an inode limit by nature, other hosting options like private or cloud hosting are not exempt from inode limits.

Another point you should keep in mind about inodes is that while hosting companies promise “unlimited” storage space for their plans, this doesn’t refer to the limit of inode storage on the account. Therefore, it’s always a good idea to check the inode limits when you’re trying to pick between hosting plans.

If you want to find out more about hosting in general, you can head over to our article on “How to Host Your Own Website: A Beginner’s Guide”.

How to Access Your Inode Usage Information

To find out the number of inodes you’re using on your hosting account, you can navigate to the management panel (like cPanel, Plesk, DirectAdmin, etc.) of your hosting account.

To access your inode usage information through cPanel, simply navigate to the “Stats” menu or if you want to see more detailed information, navigate to the “Inode Usage” menu. Checking the inode usage on your account can help you manage your files regularly so that you can avoid exceeding the inode usage limit.

What Happens When the Inode Limit Is Reached?

As mentioned above, hosting services usually set a limit for the number of inodes you can use on your account. If this limit is reached, it won’t be possible to create more files on the hosting account, which can significantly disrupt the flow of your website. Once the pre-determined inode limit is reached, it’s no longer possible to create any more files on that hosting account. 

If you start getting close to your inode limit, most hosting providers will let you know with an email along with tips to reduce your inode usage. Ignoring this warning and not reducing your inode usage may result in your hosting provider shutting down your service until:

• The inode number is below the limit again,
• You upgrade to a plan with a higher inode limit.

Exceeding the inode limit may lead to your website not working properly. In addition, it can affect your website’s SEO. When a user clicks on a link through a search engine, if the website is unresponsive and the user is unable to load the page, the search engine will keep a record of this, which may lead to your website not showing up in search results.

To learn about our inode limits per user and find a hosting plan that suits your needs, check out Domain Name Sanity’s Monthly Web Hosting plans.

How to Reduce Inode Usage

Reducing your inode usage is all about limiting the number of files you use. The more complicated your folder structure is, the more inodes you will require. Here are some of the ways in which you can limit your inode usage:

Delete Old Files and Backups

The most efficient way to reduce your inode usage is to delete old and unused files, themes, and plugins on your account. When you delete a file, its inode is also deleted. You should be aware that outdated, unnecessary plugins and themes are also included in your inode quota, and not removing these outdated files can cause you to exceed your quota.

While using themes, it’s generally recommended to only keep one active theme and delete any inactive themes. Also, try to choose a theme that doesn’t have too many features. Keep in mind that a plugin-heavy theme will use up more inodes than a theme with a few, but essential plugins. Using fewer plugins also ensures that your website loads as fast as possible.

Additionally, here are some other potentially unused file types you may want to remove that may be using up your inode limit:

• Images and videos,
• Log files,
• Bulk files.

Clean Up Your Inbox and Spam Folder

Cleaning up your inbox is another good way to cut down on your inode usage. If you have an email account that you use to send thousands of emails in an email marketing campaign and you haven’t cleared your “sent” folder, that email account could be responsible for thousands of inodes being used.

Also, there may be hundreds or even thousands of messages piling up in the spam folder of an email account you haven’t used for a while. This can quickly lead to a pile-up of inodes and these mails alone may cause you to exceed your inode limit. You can reduce your inode usage by simply cleaning up old emails or overcrowded spam folders.

The email account you are using for your hosting may not be your main personal email address. If you’d like to forward your emails on your hosting account to your personal account, you can read this article on “Free Email Forwarding on Domain Name Sanity”.

Use Cloud Storage 

Another very effective method is to use external file storage. Instead of using the outdated method of storing files on a piece of hardware, you can keep your storage directly on the internet. And the best part about cloud storage is that you can reach your storage from anywhere as long as you have an internet connection. 

Nowadays, there are many companies like Google, Amazon, and Microsoft that offer cloud storage systems. 

Remove Cache Files

The cache, which has a huge impact on your website’s speed, can also have a huge impact on your inode limit. Periodically clearing your expired cache can help you reduce the number of inodes you use. 

As a final tip: you can reduce your inode usage even more by removing the “.opcache” folder. 

Refresh the .opcache Folder by Removing It

To clear out your cache while also deleting older versions of PHP, and therefore saving up on more inode storage, you can simply delete your .opcache file. The .opcache file refers to “Obsolete cache” and when you delete it, it will be regenerated automatically. But the older, obsolete versions of the cache will be removed from your storage.