[CentOS] CUPS and virtual interfaces

I've got a server with multiple virtual interfaces. Now, I only want CUPS
to advertise on *one* - eth0, not eth0:1 or eth0:gad....

Looking at the CUPS manual, and cuppsd.conf man page, I see BrowseAllow,
but the entries are not clear enough for me to understand what they mean.
(Yeah, I know the docs are better than they were - read ESR's rant about
it from a few years ago.)

Specifically, I *think* I'd like to use BrowseAllow @IF, but I can't
figure out if that should be
BrowseAllow @IF(eth0)
or
BrowseAllow @IF(hostname)

Also, if it's interface name, and there are multiple virtual interfaces on
eth0, and I use the first of the two lines, above, will that *not* also
apply to the VIs on eth0?

        mark