[4.0] 2f05fe4 Serve ESI-includes from a different backend.

[Martin Blix Grydeland]

commit 2f05fe44f072373bd11da06b01586110412fc15c
Author: Martin Blix Grydeland <martin at varnish-software.com>
Date:   Mon Mar 3 12:51:22 2014 +0100

    Serve ESI-includes from a different backend.
    
    Serve ESI-includes from a different backend so that we don't race
    against when the backend connection is ready for reuse.
    
    Fixes: #1440

diff --git a/bin/varnishtest/tests/e00019.vtc b/bin/varnishtest/tests/e00019.vtc
index 1aeaa06..1010eab 100644
--- a/bin/varnishtest/tests/e00019.vtc
+++ b/bin/varnishtest/tests/e00019.vtc
@@ -22,13 +22,25 @@ server s1 {
 	chunked {<esi:comment/>}
 
 	chunkedlen 0
+} -start
 
+# The included object gets served from a different backend.
+# This is to avoid a race between when a backend connection
+# gets put up for reuse because of background fetches in
+# Varnish 4
+server s2 {
 	rxreq
 	expect req.url == "bar/foo"
 	txresp -body {<INCL>}
 } -start
 
 varnish v1 -vcl+backend {
+	sub vcl_backend_fetch {
+		if (bereq.url != "bar") {
+			set bereq.backend = s2;
+		}
+	}
+
 	sub vcl_backend_response {
 		if (bereq.url == "bar") {
 			set beresp.do_esi = true;