Off Topic - Sub Domain Tomcat

[customaware]

This is all gunna sound really basic but please bare with me and I really know very little about this sort of stuff....

I have Aware installed on my server at mydomain.com

I added the ROOT folder to Tomcat/webapps and put my website in there so that in a browser the url mydomain.com opens the index.html file in
Tomcat/webapps/ROOT

So far all good.

Ok... now I add a subdomain called say... demosd

in the Tomcat/conf/server.xml I add

<Host appBase="webapps/demosd" autoDeploy="false" name="demosd.mydomain.com" unpackWARs="true">
<Context antiJARLocking="true" docBase="C:\AwareIM\Tomcat\webapps\ROOT\demosd" path=""/>
</Host>

and I place the demosd website with its own index.html file in C:\AwareIM\Tomcat\webapps\ROOT\demosd

I would expect the url demosd.mydomain.com to find that page but it does not.

The only way I can get it to work is to place the demosd folder under C:\AwareIM\Tomcat\webapps and use

<Host appBase="webapps/demosd" autoDeploy="false" name="demosd.mydomain.com" unpackWARs="true">
<Context antiJARLocking="true" docBase="C:\AwareIM\Tomcat\webapps\demosd" path=""/>
</Host>

in the server.xml file and use the url mydomain.com/demosd

Can someone please suggest what I am doing wrong and how I can get demosd.mydomain.com to open index.html located in C:\AwareIM\Tomcat\webapps\ROOT\demosd ?

Or.... advise if this is completely the wrong approach?