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.neturliisurl-rewritingarr

IIS ARR reverse proxy only works for existing resource URLs

I have URL Rewrite & ARR installed in my IIS: IIS machine dashboard

And ARR proxy enabled: Server proxy setting

I have a .net app in my IIS. a local .net app site

There are 2 files in it. WebForm1.aspx and WebForm2.aspx .net project

And if I set up URL Rewrite from webform1.aspx to an external website, it works URL Rewrite rule browser log

But if I set it up with webform3.aspx, it shows 404. It's like the rule doesn't take effect for non-existing page. error page

Solution

  • If we enable failed request tracing then we will notice that the rewrite rule has succeeded.

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    Then problem is asp.net pipeline brake it.

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    If you try it on an empty website, it will work.

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    So you'd better be careful when you reverse proxy to an external website.