#4680 apache 2.4 reverse proxy login does not complete

I have configured a webmin 1.770 box to listen on 127.0.0.1:10000.
Then I followed the advice on http://www.webmin.com/apache.html

...
Webmin In A Sub-Directory Via A Proxy
...

My configuration differ only in using https instead of http.

Now If I try to login the POST request to the server hangs, If
I wait a few seconds and enter the url again I get the welcome screen.
This behavior is always repeatable.

...
192.168.xxx.xxx - - [24/Nov/2015:17:39:51 +0100] "GET / HTTP/1.1" 401 2858                      
192.168.xxx.xxx - admin [24/Nov/2015:17:39:57 +0100] "POST /session_login.cgi HTTP/1.1" 302 0
192.168.xxx.xxx - admin [24/Nov/2015:17:40:01 +0100] "GET / HTTP/1.1" 200 898                
192.168.xxx.xxx - admin [24/Nov/2015:17:40:02 +0100] "GET /right.cgi HTTP/1.1" 200 7023      
192.168.xxx.xxx - admin [24/Nov/2015:17:40:02 +0100] "GET /left.cgi HTTP/1.1" 200 16195      
...

The 3rd entry is a hit of the same url in the address bar.

Here my apache config

...
<Location /webmin/>                                            
  ProxyPass                           https://127.0.0.1:10000/ 
  ProxyPassReverse                    https://127.0.0.1:10000/ 
  ProxyPassReverseCookiePath /        /webmin                  

  RequestHeader unset Accept-Encoding                          
</Location>
...

Here the cookies:

...
sid=xxxxx; path=/webmin; domain=192.168.xxx.xxx; Secure; HttpOnly
testing=1; path=/webmin; domain=192.168.xxx.xxx; Secure; HttpOnly
...

I am using kernel 3.19.0.33 on Ubuntu 14.04.3 LTS and Apache 2.4.16

[Jamie Cameron]

What config changes did you make to /etc/webmin/config and /etc/webmin/miniserv.conf ?

It sounds like the cause is the cookie being set on the wrong path, which is either preventing your browser from sending it to Webmin, or Webmin from recognizing it.

[Anonymous]

/etc/webmin/miniserv.conf
bind=127.0.0.1
sockets=
cookiepath=/webmin

/etc/webmin/config
referer=127.0.0.1
allow=127.0.0.1
webprefix=/webmin
webprefixnoredir=1

[Jamie Cameron]

One thing you might try is switching Webmin to non-SSL mode (assuming you will never access it directly), and changing the proxy URL to http://