1. Basic Troubleshooting
Begin with some fundamental steps.
2. Things to Try on the Client Side
Although Error 503 is typically a server-side issue, the client machine might display this error due to an improper request from the client side. Let’s try the following steps to ensure that’s not the case:
Try the Website in Another Browser
Use Another Network or Try a VPN
Visit the Stable Version of the Website
Some websites have alpha or beta versions that are used for testing. These versions might be unstable, leading to the first-byte timeout error. To circumvent this, try accessing the stable version of the website. The process will vary based on the website and browser settings.
Check Your User Actions
You might receive the Error 503 if you attempt to perform an action that the server does not allow. For instance, if the website only permits uploading JPEG images, trying to upload a PNG file could trigger the first-byte timeout error. The solution here is straightforward: upload a JPEG image. Depending on your situation, you may need to investigate further to identify user actions that could be causing the error.
3. Server Side
If users encounter Error 503 first-byte timeout when trying to access your website, you can employ the following methods:
Check Limits
Firstly, review the timeout limits set for your website or server. You may need to adjust these values, and the procedure will depend on the technology or server architecture in use.
Varnish
Fastly
Magento
Check Server Extensions
The issue might stem from a server extension. Disabling or removing any questionable extensions may solve the problem. The PCNTL extension is known to cause Error 503. If such or similar extensions are present, disabling or removing them is advisable. Be aware that disabling or removing an extension can temporarily affect certain website functionalities. To pinpoint the culprit, you may need to deactivate extensions one at a time.
Test Response Headers for Nginx
Check Your Subscription Plan
Should your server be unable to access essential services due to subscription limitations, this could result in a first-byte timeout error. As an illustration, under the Spark payment plan, servers are unable to make external HTTP requests to non-Google services. An upgrade of your subscription plan might be necessary to resolve this issue, for example, switching from Spark to the Blaze plan in Firebase.
Check for a DDoS Attack
If the website server or any of its backend dependencies are under a DDoS attack, the server may not be able to obtain the required responses, leading to a first-byte timeout error for users. Investigate potential DDoS attacks against your website, hosting, or any backend technology such as Webflow. Should none of the suggested solutions work, reach out to the Support team of your hosting or backend services provider. Additionally, check the status page of the hosting’s website for any known issues.
