<div dir="ltr"><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">It doesn't seem to work. Take the example of HTTP 404 from backend, it actually goes to vcl_backend_response, not vcl_backend_error.</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small">And unfortunately I am not allowed to use synthetic() in vcl_backend_response. Inside vcl_backend_response I also thought of passing a custom header beresp.http.X-CustomError = "YES" to vcl_deliver, but it's the same result that I am not allowed to use synthetic() in vcl_deliver.</div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Thu, Oct 9, 2014 at 11:45 PM, Per Buer <span dir="ltr"><<a href="mailto:perbu@varnish-software.com" target="_blank">perbu@varnish-software.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><br><div class="gmail_extra"><br><div class="gmail_quote">On Thu, Oct 9, 2014 at 4:58 PM, Kelvin Loke <span dir="ltr"><<a href="mailto:kelvin1111111@gmail.com" target="_blank">kelvin1111111@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><div dir="ltr"><div style="font-family:arial,helvetica,sans-serif;font-size:small">I used to be able to do it in Varnish 3, but it's no longer an easy task in Varnish 4 (or my weary mind stops me from figuring out).</div><div style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div style="font-family:arial,helvetica,sans-serif;font-size:small">How can I customized the error page (403, 404, 500, etc) from backend and send to end users? I prefer not to let the public to view my application error content.<span style="font-family:arial"> </span></div></div></blockquote><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><div dir="ltr"><div style="font-family:arial,helvetica,sans-serif;font-size:small"><br></div><div style="font-family:arial,helvetica,sans-serif;font-size:small">In Varnish 3 I am able to return the error() and specify the customized error message in vcl_error. However in Varnish 4 I can't find any way to return the synth() in vcl_backend_response and vcl_backend_error and specify the custom message in vcl_synth().</div></div></blockquote><div><br></div><div>Have a look at "builtin.vcl" in the distribution. You'll find:</div><div><br></div><div># sub vcl_backend_error {</div><div># set beresp.http.Content-Type = "text/html; charset=utf-8";</div><div># set beresp.http.Retry-After = "5";</div><div># synthetic( {"<!DOCTYPE html></div><div># <html></div><div># <head> </div><div><br></div><div><br></div><div>You should be able to override it.</div></div><span class="HOEnZb"><font color="#888888"><div><br></div>-- <br><div dir="ltr"><table border="0" cellpadding="0" cellspacing="0" style="border-bottom-width:1px;padding-top:5px;border-top-style:solid;width:550px;padding-bottom:5px;border-bottom-color:rgb(238,238,238);border-top-width:1px;border-bottom-style:solid;line-height:1.5em;border-top-color:rgb(238,238,238);color:rgb(102,102,102);font-size:12px;font-family:'Helvetica Neue',Arial,sans-serif;margin-top:20px"><tbody><tr><td width="100"><img src="http://www.varnish-software.com/static/media/logo-email.png"></td><td><font color="#222222"><span style="font-size:14px"><b>Per Buer</b></span></font><br>CTO | Varnish Software AS<br>Cell: <a value="+4790181750" style="color:rgb(17,85,204)">+47 95839117</a><br><span style="font-weight:bold">We Make Websites Fly!<br><a href="https://www.varnish-software.com/" style="color:rgb(17,85,204)" target="_blank">www.varnish-software.com</a></span></td></tr></tbody></table><br><div style="color:rgb(136,136,136)"><a href="http://info.varnish-software.com/varnish-summits-autumn-2014-registration" style="color:rgb(17,85,204)" target="_blank"><img src="https://www.varnish-software.com/sites/default/files/u388/masters_s_0.png" alt=" Register now"></a></div></div>
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