Internet: 502 Bad Gateway response

Self-tutoring about Internet surfing: the tutor mentions an error code he received.

I clicked on a link to a website today and received a “502 Bad Gateway” error. What did it mean, I wondered, so decided to look it up.

Apparently, the 502 Bad Gateway response means the following situation:

1. The request (the click on the link) went to a server that acts as a gateway rather than the primary source of the content.
2. The server in (1) then passed on the request to the server that dispenses the content.
3. The server that is meant to dispense the content sent an invalid, perhaps non-meaningful, response instead.
4. The gateway server, with nothing to provide to the requester, sent back 502 Bad Gateway.

The name is somewhat ironic, perhaps, since it seems that the gateway isn’t what’s failing, but rather the server beyond the gateway that was meant to send along the content. Yet, such is my understanding.

Source:

developer.mozilla.org