🚂
527
Railgun Error
Example HTTP Response
HTTP Response
HTTP/1.1 527 Railgun Listener Error
Server: cloudflare
Content-Type: text/html
<html><body>Error 527: Railgun Listener error</body></html>Common Causes
- Railgun listener not responding
- Railgun service crashed or stopped on origin
- Firewall blocking Railgun connection (port 2408)
- Railgun listener timeout
- Railgun software misconfigured
- Origin server resources exhausted affecting Railgun
- Network issues between Cloudflare and Railgun listener
Technical Details
What does this mean?
The express train broke down! Cloudflare tried to use the super-fast Railgun connection to your origin but the rail line is having issues. Time to call maintenance!
Technical Definition
The request failed after Cloudflare established a connection to the origin Railgun server. Railgun is Cloudflare's deprecated WAN optimization technology.
Code Snippets
Ready-to-use code for returning this HTTP status in your application:
Node.js
// Express.js
app.get('/example', (req, res) => {
res.status(527).json({
error: 'Railgun Error',
message: 'Your error message here'
});
});
// Native HTTP
const http = require('http');
http.createServer((req, res) => {
res.writeHead(527, { 'Content-Type': 'application/json' });
res.end(JSON.stringify({
error: 'Railgun Error',
message: 'Your error message here'
}));
}).listen(3000);Related Status Codes