<div dir="ltr">Gotcha - I'll upgrade to 5 shortly, but I don't think that's affecting my confusion.<br clear="all"><div><br></div><div>Thanks for your nitpick, I think it's actually part of the key. I followed your suggestion, trying the parent cache_peer just on http, with the following squid.conf. <br><br>http_port 80 accel<br>cache_peer 10.60.4.178 parent 3128 0 no-query no-digest name=forward<br>request_header_add Joel Joel<br><br># Simplified acl<br>http_access allow all<br>cache_peer_access forward allow all<br><br># Misc<br>shutdown_lifetime 1 seconds<br>debug_options ALL,6<br><br>I upped the log level and followed how squid transformed the request, and saw it change</div><div><br>GET / to <br>GET its-own-hostname/<br><br>based on the Host header on the incoming request, as you pointed out. </div><div><br></div><div>The first problem is, the parent proxy doesn't know how to resolve that host - it rejects the request with "Invalid URL". I need the reverse proxy to rewrite both the host header and url to their correct target values for the parent proxy.</div><div><br></div><div>I tested this via telnet to the parent proxy (since I'm still struggling to get squid url rewriting working, will try that more later). When I sent<br><br>GET <a href="http://target-hostname/">http://target-hostname/</a> HTTP/1.1<br>User-Agent: curl/7.68.0<br>Accept: */*<br>Host: target-hostname<br>Via: 1.1 ip-10-60-4-103 (squid/3.5.27)<br>Surrogate-Capability: ip-10-60-4-103="Surrogate/1.0 ESI/1.0"<br>X-Forwarded-For: 10.40.0.194<br>Cache-Control: max-age=259200<br>Connection: keep-alive<br>Joel: Joel<br></div><div><br></div><div>it works, but if I try https I get "Unsupported Request Method and Protocol" (it so happens that the parent proxy is also a squid in this case). I think this is expected, as the request above (https from proxy to proxy, on behalf of http client) should have been a CONNECT followed by the GET once the tunnel was established.</div><div><br></div><div>So: is squid capable of receiving the GET / to itself, sending a CONNECT /target-hostname to the parent proxy, negotiating that connection and then returning the result to the client? Obviously when it's functioning as a forward proxy it can <i>receive</i> CONNECTs and handle them, but this is the "flip" I'm still struggling with. </div><div><br>Thanks so much for your time, I'm learning this as I go and you've been very helpful.</div><div><br></div>-- <br><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><p><span style="font-family:Titillium Web,sans-serif"><span style="font-size:16px"><strong><span style="color:#0e3179">Joel Howard</span></strong></span></span><br>
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<font color="#1155cc"><a href="mailto:jhoward@tetrascience.com" target="_blank">jhoward@tetrascience.com</a></font><font color="#0e3179"><b> </b></font></span></span><span style="color:#0e3179"><span style="font-weight:400"><span style="font-style:normal"><span style="text-decoration:none">| </span></span></span></span></span></span></span></span><span style="font-size:9.5pt"><span style="font-variant:normal"><span style="white-space:pre-wrap"><span style="font-family:'Titillium Web',sans-serif"><span style="color:#30c2dc"><span style="font-weight:400"><span style="font-style:normal"><span style="text-decoration:none">(330) 209-5779</span></span></span></span></span></span></span></span></p>

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