What is the 5xx Status Code?
5xx status codes – often called “5xx server error” - indicate the errors that happen when someone tries to access your website but the server is unable to complete the request and show the website.
You will see one of the error codes from the 5xx range. This may happen for many reasons like server time out, server misconfiguration, or a bad gateway.
Remember, a series of processes are taking place to process the HTTP request, so a server error can occur at any point in a server setting or environment.
Common Types of 5xx Status Codes
Here is a list of the most common 5xx error codes that are needed to understand from an SEO point of view.
500 Internal server error
While browsing on the internet, you must have experience pages with this message:
500 Internal Server Error
500 Server Error
500. That's an error.
Error 500
Error code: 500
500 Internal server error is the most common one that shows there is something wrong with the server, but the exact cause is unknown.
The server does not process the request, which can happen due to many technical reasons, i.e. software incompatibility, corrupted .htaccess file, bugs etc.
501 Not Implemented
This shows that the server is unable to process the request because it does not support the HTTP request sent by the client.
502 Bad Gateway
This error occurs when the server acts as a gateway or proxy server. This shows that the upstream server – from where a response is expected - has not responded properly, so the request cannot be processed.
503 Service Unavailable
503 is just a temporary error that occurs due to server overloading or maintenance.
504 Gateway timeout
This is almost similar to 502. In 504 gateway timeout, the server acting as a proxy or gateway does not get a response from the upstream server in a given time frame.
The slight difference between 502 and 504 is that in 502, the server is unable to get a valid response from the upstream server, whereas, in the latter, the server is unable to get a response at all within a given time period.
505 HTTP Version Not Supported
This error is what it states in its name – HTTP Version Not Supported. It occurs when the HTTP protocol sent by the client is not supported by the server. This error will also explain in its response why this has occurred.
506 Variant Also Negotiates
“506 variant also negotiates” indicates that the server (supporting multiple variants) is showing the most appropriate version of a resource.
507 Insufficient Storage
This is also a temporary error showing that the server cannot process the request due to insufficient storage.
508 Loop Detected
This error occurs when the server tries to process a request, but an “infinite loop” exists, and as a result, the entire operation will be failed.
510 Not Extended
This error indicates that the server needs a further extension to process the request sent by a client.
511 Network Authentication Required
As the name indicates, this error occurs when the client must authenticate itself to fully access a network.
524 A timeout occurred
524 is a Cloudflare-specific error which occurs when the origin server fails to respond in time. As a result, Cloudflare is unable to show responses to both bots and searchers.
What causes 5xx errors?
5xx errors show the server's failure to respond to a request. It can occur due to the following reasons:
Server misconfiguration: It is one of the leading causes of errors which occur due to server misconfiguration.
Failure of CDN: A misconfiguration of CDN (Content Delivery Network) also results in server errors, i.e. Cloudflare, Akamai, etc.
Bugs: Several bugs may cause an error, i.e. Apache, Nginx, etc.
Failure of CMS: An error due to failure of CMS (Content Management System) can result in server errors. It may also occur when a web development framework is not compatible with a CMS, i.e. PHP, .NET, etc.
Incompatible plugins: Server errors may occur due to faulty or incompatible plugins on WordPress websites.
Coding errors: If files that are trying to be accessed are not coded properly, they can also lead to server errors.
Heavy traffic loads: Sometimes, when there is a sudden traffic load on a website, the server cannot handle it properly and crashes.
Server errors may occur for several other reasons during the HTTP request process. These are easy to resolve if they correctly identify where the errors have actually occurred.
Why should you fix 5xx errors?
If one or many URLs on your website show the 5xx errors, it will prevent the crawlers and searchers from accessing your website pages.
Crawlers will most likely abandon the request, while searchers will leave the website. As a result, it will have a negative impact on your website in terms of SEO and user experience.
If the 5xx errors stay there for longer, crawlers like Googlebot will gradually increase the time to crawl these URLs again and ultimately drop them from its index.
How to find 5xx server errors?
Identifying these errors can be difficult, especially if there are thousands of pages on your website. 5xx errors are bad for your website, so here are the simplest methods to identify them.
Crawl Stats Report
You can find the 5xx errors on different URLs of your website by going to Crawl Stats Report in GSC.
Go to Google Search Console ˃ Settings ˃ Open Report
See the “By response” under "Crawl request breakdown” and then see Server errors (5xx)
Index Coverage Report
Go to Google Search Console and add your property. Skip this step if you have already connected your website with GSC.
Go to Index ˃ Coverage ˃ Error
See the Error category for any 5xx error pages on your website.
Screaming frog
You can also use a website crawler like screaming frog to crawl your entire website. It will present a huge amount of helpful information.
Allow Screaming Frog’s SEO Spider to crawl your website.
Select the Response Codes option at the top and go to Server Error (5xx). It will show you a list of all 5xx errors Screaming Frog has encountered on your website.
Server Log Files
You can find the server errors by directly going to your server log files to see the requests made by the client and how the server has responded.
The server log files are extremely valuable, so you must handle them carefully. They provide a detailed overview of server errors, and even those Google hasn’t encountered.
This process is time-consuming as you will be required to open the individual files that could be present at different locations. It will also depend upon the type of server you are running, so you can access your cPanel or ask your server administration to access log files.
How to fix the 5xx server error?
Once you have identified the 5xx errors, you can adopt the following steps.
Sometimes, a 5xx error is temporary; simply reloading a page will bring it to track. Keep in mind this only works when a server error is temporary.
Another possible cause can be related to website cookies. Clear the cookies and reload your website. If the error still appears even after clearing the cookies, there is another reason.
If you have recently made changes to your website, installed a plugin, updated software, or encountered unsuccessful upgrades - it can be a possible cause of 5xx errors, especially if a plugin is not compatible with your CMS or a file is missing or corrupted during an upgrade. Just roll back your updates or any changes you have recently made and see whether it is giving the error or not.
If all this is not working for you, now it’s time to contact your web developer or ask your hosting company to resolve the issue.
Takeaway
5xx errors occur when a server is unable to process a request. Every website owner may expect to face 5xx errors – some are temporary, while some are quite serious and require urgent attention.
Google does not like 5xx errors; if it encounters these errors (especially 500 and 503), it may ultimately remove your website from indexing.
These errors can be identified by Google Search Console or using site audit tools like Screaming Frog.