SBN - Proxy Server Notes

Reverse Proxy (Outside Access to internal servers)

Start with a standard Web Server install...

We'll be basing our procedure on Configuring Apache To Proxy Connections

Enable the proxy modules:

• sudo a2enmod proxy proxy_ajp proxy_http rewrite deflate headers proxy_balancer proxy_connect proxy_html

(possibly add mod_authz_host to the list...)

Create the virtual machine to point incoming connections at the internal server you want to proxy:

• sudo vim /etc/apache2/apache2.conf

& add this (modified to suit) to the end of the file:

<VirtualHost *:80>
    ServerName MyServer.MyDomain.net
    Redirect permanent / https://MyServer.MyDomain.net/
</VirtualHost>

<VirtualHost _default_:443>
    ServerName MyServer.MyDomain.net
    ProxyRequests on
    SSLEngine On
    SSLProxyEngine On
    ProxyPreserveHost On

    ProxyPass / https://MyServer.MyDomain.net/
    ProxyPassReverse / https://MyServer.MyDomain.net/
SSLCertificateFile /etc/letsencrypt/live/MyServer.MyDomain.net/fullchain.pem
SSLCertificateKeyFile /etc/letsencrypt/live/MyServer.MyDomain.net/privkey.pem
    <Proxy "*">
        Order allow,deny
        Allow from all
    </Proxy>
        ErrorLog /var/log/apache2/Proxy/MyServer_log
        CustomLog /var/log/apache2/Proxy/MyServer-access_log combined

</VirtualHost>

You will need to set up external DNS for MyServer.MyDomain.net (which is NOT the same as your normal webserver name as far as the outside world is concerned)

You may have noted that we're pointing at a set of cert files that need to be on the machine.

• sudo mkdir /etc/letsencrypt/live/MyServer.MyDomain.net

& copy the certs from the internal server into this folder. (see CertGetter for information about getting certs for internal machines)

Also, 2 log files in a new folder...

• sudo mkdir /var/log/apache2/Proxy

(this folder will be populated automgically when you restart Apache...)

Now, restart Apache:

• sudo service apache2 restart

At this point, you should be able to browse to MyServer.MyDomain.net from outside your network.

Access Control by IP

You can control who can access your proxy via the <Proxy> control block as in the following example:

<Proxy "*">
  Require ip 192.168.0.1
</Proxy>

Simply replace 192.168.0.1 with the IP of the machine allowed to access this proxy.

Upcoming tricks...

• Special considerations for the ESXi WebUI
• Multi-Site Server Management from a Central Server

Further Reading

• Apache Module mod_proxy
• Apache Module mod_authz_host