Proxying and using alternate host names with Apache

After spotting this comment on StatusNet saying about using another port on the same IP address for a web service, I thought I’d jot down what I do instead, to ensure I use the standard HTTP and HTTPS ports for my web applications.

In /etc/apache2/sites-available, I create a file called subdomain.your.host.name

<VirtualHost *:80>
    ServerAdmin webmaster@localhost
    ServerName subdomain.your.host.name

    ErrorLog ${APACHE_LOG_DIR}/subdomain.your.host.name.error.log

    # Possible values include: debug, info, notice, warn, error, crit,
    # alert, emerg.
    LogLevel warn

    CustomLog ${APACHE_LOG_DIR}/subdomain.your.host.name.access.log combined

    ProxyPass / http://127.0.0.1:12345/
    ProxyPassReverse / http://127.0.0.1:12345/
</VirtualHost>

Configure your non-apache app to bind to a port on 127.0.0.1, here I’ve set it to 12345

This proxies an HTTP only application… but if you want to proxy an HTTPS application, you either need to have a wildcard SSL certificate, use multiple IP addresses, or, as the original post suggested, use an alternate port.

If you’re proxying an application for HTTPS, try this:

<IfModule mod_ssl.c>
<VirtualHost *:443>
    ServerAdmin webmaster@localhost
    ServerName subdomain.your.host.name

    ErrorLog ${APACHE_LOG_DIR}/ssl_subdomain.your.host.name.error.log
    LogLevel warn
    CustomLog ${APACHE_LOG_DIR}/ssl_subdomain.your.host.name.access.log combined

    SSLEngine on
    SSLCertificateChainFile /etc/openssl/root.crt
    SSLCertificateFile /etc/openssl/server.crt
    SSLCertificateKeyFile /etc/openssl/server.key

    BrowserMatch "MSIE [2-6]" \
        nokeepalive ssl-unclean-shutdown \
        downgrade-1.0 force-response-1.0
    # MSIE 7 and newer should be able to use keepalive
    BrowserMatch "MSIE [17-9]" ssl-unclean-shutdown

    ProxyPass / http://127.0.0.1:4670/
    ProxyPassReverse / http://127.0.0.1:4670/
</VirtualHost>
</IfModule>

Of course, if you’re looking to create several virtual hosts for apache, rather than proxy them, you can instead do this:

<VirtualHost *:80>
    ServerName subdomain.your.host.name
    ServerAdmin webmaster@localhost

    DocumentRoot /var/www_subdomain.your.host.name/
    <Directory />
        Options FollowSymLinks
        AllowOverride None
    </Directory>

    <Directory /var/www_subdomain.your.host.name/>
        Options Indexes FollowSymLinks MultiViews
        AllowOverride All
        Order allow,deny
        allow from all
    </Directory>

    ErrorLog ${APACHE_LOG_DIR}/subdomain.your.host.name.error.log

    # Possible values include: debug, info, notice, warn, error, crit,
    # alert, emerg.
    LogLevel warn

    CustomLog ${APACHE_LOG_DIR}/subdomain.your.host.name.access.log combined

</VirtualHost>

Once you’ve got your config files up, you’ll need to enable them with the following command:

a2ensite subdomain.your.host.name

That assumes you named the file /etc/apache2/sites-available/subdomain.your.host.name

You may need to enable the proxy module with the command:

a2enmod proxy