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herokuloggingpapertrail-app

What does fwd mean in the heroku logs?

Inside the heroku logs, I have the following line...

Aug 06 21:50:18 coolApp heroku/router:  at=info method=GET path="/about.jpg" host=coolapp.com fwd="78.7.88.177,643.198.55.55" dyno=web.1 connect=0ms service=43ms status=500 bytes=420

My question is what does fwd represent? I see they are IP addresses. Are they IP addresses from the user?

Solution

  • From heroku docs:

    fwd: HTTP request X-Forwarded-For header value

    From Wikipedia:

    The X-Forwarded-For (XFF) HTTP header field is a common method for identifying the originating IP address of a client connecting to a web server through an HTTP proxy or load balancer.

    So I think you are right when the http requests are from a user's browser.