wget mirror all subdomains

Question

I am mirroring a website starting my crawl from a particular subdomain (eg a.foo.com).
How can I make wget also download content from other linked subdomains (eg b.foo.com) but not external domains (eg google.com)?

I assumed this would work:

wget --mirror --domains="foo.com" a.foo.com

However links to b.foo.com were not followed.

Answer 1

you'd need to add -H as well (enable spanning of hosts when doing recursive downloads) -D "foo.com,b.foo.com" -H

Answer 2

why not try httrack? it has the option to define how to deal with external link.