Introduction
Not every 500 error is caused by a faulty plugin. Sometimes the server is simply overloaded: logs, old archives, backups, temporary files, CMS cache, and database dumps take up all the space. As a result, the application cannot create a session, write to the cache, accept an upload, or update a table.
Symptoms
From the outside, it looks like a sudden crash. The site keeps going up and down; the admin panel doesn’t save settings; the contact form doesn’t save entries; email stops accepting attachments; the database complains about being unable to write. If there’s absolutely no space left, even error logging might not work properly.
What is being checked
- How much free space is left on the partitions?
- Have we run out of inodes?
- Which catalogs are growing the fastest?
- Is web server and PHP log rotation configured?
- Where are the backups stored, and how many archives are there?
- Are the backups being copied to the same website directory?
- What kind of write errors are there in the database, PHP, and CMS?
Correction Process
First, determine exactly what is taking up disk space. You shouldn’t blindly delete the “largest files”—you could end up deleting a current backup or application data. After safely clearing the disk, configure log rotation, set a storage limit for archives, move backups off-site, and monitor the cache size. If the problem recurs, add free space monitoring.
Normal result
After the fix, the site should not only load but also retain its data: forms, sessions, cache, media, and CMS entries. A separate record is kept of which directories were the source of the growth and how many archives are now stored.
Conclusion
A full disk is a silly—but very costly—reason for a system crash. It’s easy to prevent if you have disk rotation, a clear backup policy, and monitoring in place—rather than manually cleaning it out every six months.