I've set up my Varnish server as follows:
backend web1 {.host = "XXX.XXX.XXX.XXX"; .port = "80";}
backend web2 {.host = "XXX.XXX.XXX.XXX"; .port = "80";}
backend web3 {.host = "XXX.XXX.XXX.XXX"; .port = "80";}
backend web1_ssl {.host = "XXX.XXX.XXX.XXX"; .port = "443";}
backend web2_ssl {.host = "XXX.XXX.XXX.XXX"; .port = "443";}
backend web3_ssl {.host = "XXX.XXX.XXX.XXX"; .port = "443";}
director default_director round-robin {
{ .backend = web1; }
{ .backend = web2; }
{ .backend = web3; }
}
director ssl_director round-robin {
{ .backend = web1_ssl; }
{ .backend = web2_ssl; }
{ .backend = web3_ssl; }
}
# Respond to incoming requests.
sub vcl_recv {
# Set the director to cycle between web servers.
set req.grace = 120s;
if (req.http.X-Forwarded-Proto == "https" ) {
set req.http.X-Forwarded-Port = "443";
set req.backend = ssl_director;
} else {
set req.http.X-Forwarded-Port = "80";
set req.http.X-Forwarded-Proto = "http";
set req.backend = default_director;
}
...
}
This works perfectly if I hit my IP address (without SSL) in the browser, but if I enable Pound (config below):
ListenHTTPS
Address XXX.XXX.XXX.XXX #Local IP of the VarnishWebServer
Port 443
Cert "/etc/apache2/ssl/apache.pem"
AddHeader "X-Forwarded-Proto: https"
HeadRemove "X-Forwarded-Proto"
Service
BackEnd
Address 127.0.0.1
Port 80
End
End
End
I get a 503 everyime I try to hit the local IP address (from varnishlog -0):
11 RxURL c /favicon.ico
11 RxProtocol c HTTP/1.1
11 RxHeader c Host: XXX.XXX.XXX (Varnish Server IP Address)
11 RxHeader c Connection: keep-alive
11 RxHeader c Accept: */*
11 RxHeader c User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/32.0.1700.107 Safari/537.36
11 RxHeader c Accept-Encoding: gzip,deflate,sdch
11 RxHeader c Accept-Language: en-US,en;q=0.8
11 RxHeader c X-Forwarded-Proto: https
11 RxHeader c X-SSL-cipher: DHE-RSA-AES128-GCM-SHA256 TLSv1.2 Kx=DH Au=RSA Enc=AESGCM(128) Mac=AEAD
11 RxHeader c X-Forwarded-For: XXX.XXX.XXX.XXX (My Local machine IP)
11 VCL_call c recv lookup
11 VCL_call c hash
11 Hash c /favicon.ico
11 Hash c 198.61.252.81
11 VCL_return c hash
11 VCL_call c miss fetch
11 Backend c 14 ssl_director web2_ssl
11 FetchError c http read error: -1 0 (Success)
11 VCL_call c error deliver
11 VCL_call c deliver deliver
11 TxProtocol c HTTP/1.1
11 TxStatus c 503
11 TxResponse c Service Unavailable
11 TxHeader c Server: Varnish
...
11 ReqEnd c 1175742305 1391779282.930887222 1391779282.934647560 0.000097752 0.003678322 0.000082016
11 SessionClose c error
I looked at my http listeners and I see this:
root@machine:/etc/apache2/ssl# lsof -i -n|grep http
pound 7947 www-data 5u IPv4 63264 0t0 TCP XXX.XXX.XXX.XXXX:https (LISTEN)
pound 7948 www-data 5u IPv4 63264 0t0 TCP XXX.XXX.XXX.XXXX:https (LISTEN)
varnishd 8333 nobody 7u IPv4 64977 0t0 TCP *:http (LISTEN)
varnishd 8333 nobody 8u IPv6 64978 0t0 TCP *:http (LISTEN)
varnishd 8333 nobody 13u IPv4 65029 0t0 TCP XXX.XXX.XXX.XXXX:37493- >YYYY.YYYY.YYYY.YYYY3:http (CLOSE_WAIT)
apache2 19433 root 3u IPv4 31020 0t0 TCP *:http-alt (LISTEN)
apache2 19438 www-data 3u IPv4 31020 0t0 TCP *:http-alt (LISTEN)
apache2 19439 www-data 3u IPv4 31020 0t0 TCP *:http-alt (LISTEN)
pound 19669 www-data 5u IPv4 31265 0t0 TCP 127.0.0.1:https (LISTEN)
pound 19670 www-data 5u IPv4 31265 0t0 TCP 127.0.0.1:https (LISTEN)
Where XXX.XXX.XXX.XXX is the varnish's WebServer's internal IP address, and YYYY.YYYY.YYYY.YYY is the IP address of one of the backend system defined in the VCL.
Any idea why I keep getting 503s?
UPDATE
As noted Varnish doesn't support SSL, so using Pound can transfer the traffic from 443 to 80, but when it's finished - it can't use port 443 (ssl_diretector) to serve the traffic. Removing the ssl_director and making default_director the primary, worked perfectly.
Varnish does not support HTTPS for its backend requests - any communication between Varnish and Apache must be plain HTTP.
What I found works best is to configure Apache to speak plain HTTP on port 443. This allows Apache to generate correct URLs, such as when it needs to redirect the browser.
Here's how you might configure it:
# Listen on port 443, but speak plain HTTP
Listen X.X.X.X:443 http
# Setting HTTPS=on is helpful for ensuring correct behavior of scripting
# languages such as PHP
SetEnvIf X-Forwarded-Proto "^https$" HTTPS=on
<VirtualHost X.X.X.X:443>
# Specifying "https://" in the ServerName ensures that whenever
# Apache generates a URL, it uses "https://your.site.com/" instead
# of "http://your.site.com:443/"
ServerName https://your.site.com
</VirtualHost>
You will of course need to remove any mod_ssl directives from your Apache configuration.