Why is my site displaying a "503 Service Temporarily Unavailable" error?
This is most likely caused by your site having met its maximum concurrent connection limit. Shared hosting accounts are subject to the following limits:
Linux
- Linux Economy - 50 Concurrent Connections
- Linux Deluxe - 100 Concurrent Connections
- Linux Unlimited - 200 Concurrent Connections
Windows
- Windows Economy - 50 Concurrent Connections
- Windows Deluxe - 100 Concurrent Connections
- Windows Unlimited - 150 Concurrent Connections
Our 4GH® accounts allow many more connections. This number varies, but is at the following minimum amounts:
Linux 4GH limits
- Linux 4GH Economy: 150 connections or more
- Linux 4GH Deluxe: 300 connections or more
- Linux 4GH Unlimited: 600 connections or more
Windows 4GH limits
- Windows 4GH Economy: 150 connections or more
- Windows 4GH Deluxe: 300 connections or more
- Windows 4GH Unlimited: 450 connections or more
MySQL connections are limited to 200 from your hosting server to the MySQL server.
MSSQL connections are limited to 100 concurrent connections.
Larger files also cause connections to remain open longer, while your site's visitors download them. Smaller files/text lead to shorter connections. As an example, a blog with fewer readers might perform fine with an economy account and its 50 concurrent connections. However, a blog with streaming media or a higher patronage would probably need more connections.
To resolve these issues, consider upgrading to a plan with a higher concurrent connection limit. See Upgrading or Downgrading Your Hosting Account.