Is there any way to group hosts so that a group can be specified in the serverclass.conf whitelist/blacklist rather than hostname regexes? Past a certain number of hosts using regexes like that gets complex and needs to be repeated for each stanza. I'd rather set up a 'webserver' group and throw all my web servers in it and then use that for the various stanzas that want to address those servers.
You may group servers by:
You can also group them by the type of operating system.
-http://docs.splunk.com/Documentation/Splunk/latest/admin/Serverclassconf
...so if you have servers named like web01 and web02, you can include them with one whitelist
whitelist.0=web\d{2}
or
whitelist.0=web0(1|2)
etc.
You may also set the clientName to 'webserver' on each box in deploymentclient.conf, such that you could use
whitelist.0=webserver
You can often achieve the result via inheritance - but I see your point. It is not possible to explicitly say one serverclass contains another serverclass. This would be a great enhancement request.
Those are all 'specify or filter host' solutions with no re-use between stanzas, so it seems the answer is "no, no groups"?