Apache Name Virtual Host with SSL

Question

I am attempting to setup our servers to allow traffic over SSL. I am aware that SSL does not work with Name Virtual Host, but we have all of our apache servers on virtual machines with dedicated private IPs. We have a primary virtual machine that has mod_proxy setup to route traffic to the appropriate vms.

However, in order to route https traffic we need to have the certificate installed on the proxy as well as the vms. We have a wildcard certificate that can be used across all of our hosts. Everything appears to work properly, but I receive the following in the apache logs for the proxy:

[warn] Init: SSL server IP/port conflict: host1.domain.com:443 (/etc/apache2/sites-enabled/host1:1) vs. host2.domain.com:443 (/etc/apache2/sites-enabled/host2:1)

There is one of these error message for each host we have setup on the proxy. Our Virtual Host setup for the proxy is posted below:

<VirtualHost ipaddress:443>
    ServerName host1.domain.com
    ProxyPreserveHost On
    ProxyRequests Off
    ProxyPass / https://privateip:443/
    ProxyPassReverse / https://privateip:443/

    SSLProxyEngine on
    SSLEngine on
    SSLCertificateFile /etc/ssl/certs/server.crt
    SSLCertificateKeyFile /etc/ssl/private/server.key
</VirtualHost>

Is there any way that I can get this to work?

Thanks,
~James Armes

Answer 1

It sounds like Apache is warning you that you have multiple <VirtualHost> sections with the same IP address and port... as far as getting it to work without warnings, I think you would need to use something like Server Name Indication (SNI), a way of identifying the hostname requested as part of the SSL handshake. Basically it lets you do name-based virtual hosting over SSL, but I'm not sure how well it's supported by browsers. Other than something like SNI, you're basically limited to one SSL-enabled domain name for each IP address you expose to the public internet.

Of course, if you are able to access the websites properly, you'll probably be fine ignoring the warnings. These particular ones aren't very serious - they're mainly an indication of what to look at if you are experiencing problems

Answer 2

You may be able to replace the:

VirtualHost ipaddress:443

with

VirtualHost *:443

You probably need todo this on all of your virt hosts.

It will probably clear up that message. Let the ServerName directive worry about routing the message request.

Again, you may not be able to do this if you have multiple ip's aliases to the same machine.

Answer 3

Apache doesn't support SSL on name-based virtual host, only on IP based Virtual Hosts.

Source: Apache 2.2 SSL FAQ question Why is it not possible to use Name-Based Virtual Hosting to identify different SSL virtual hosts?

Unlike SSL, the TLS specification allows for name-based hosts (SNI as mentioned by someone else), but Apache doesn't yet support this feature. It supposedly will in a future release when compiled against openssl 0.9.8.

Also, mod_gnutls claims to support SNI, but I've never actually tried it.

Answer 4

As far as I know, Apache supports SNI since Version 2.2.12 Sadly the documentation does not yet reflect that change.

Go for http://wiki.apache.org/httpd/NameBasedSSLVHostsWithSNI until that is finished