502 errors, upstream sent too big header

[assistlydavid]

We're having the same problem:

    upstream sent too big header while reading response header from
upstream

Where:

    upstream: "passenger:unix:/passenger_helper_server:"

I tried every one of proxy_buffers, proxy_busy_buffers_size,
proxy_buffer_size, fastcgi_buffers, fastcgi_busy_buffers_size,
fastcgi_buffer_size, large_client_header_buffers.

Isn't this error message coming from nginx, complaining about the size
of the header returned from passenger?  Given that, surely there's some
way I can tell nginx to allow a larger header size?

Any suggestions?

Cheers,
David.

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,188352,210626#msg-210626