Google, Yahoo, and Microsoft all announced this morning that they’re supporting an addition to the Sitemaps protocol that makes it easier for site owners with multiple subdomains to manage sitemap files.
In the past, you were forced to maintain an XML sitemap in the same domain as the domain which it referred to. i.e. www.hallme.com would have a sitemap for this domain, and blog.hallme.com would also need its own sitemap hosted on its own domain. There was no way to specify that we wanted blog.hallme.com to have a sitemap hosted on www.hallme.com, nor could we for www.hallblog.com.
For most site owners, this isn’t much of an issue, but if your business consists of multiple web properties, or many subdomains, the management of the sitemaps protocol could be quite a chore! (Imagine a scalable CMS such as wordpress.com).
The update makes life a lot easier for webmasters in these situations. Now, you can host all of your sitemaps for multiple domains at a single domain, and then use your robots.txt file to point search engines to the location of the correct sitemap.
So let’s say we want www.masterdomain.com to have the sitemap for subdomain.masterdomain.com. All you need to do is add the following line to the robots.txt file on subdomain.masterdomain.com:
On the same token, www.masterdomainblog.com could have this line added to the robots.txt:
For the average small business, this is an interesting, if useless feature, but for businesses spanning multiple web properties, with subdomains, or for businesses like ourselves who manage sitemaps for hundreds of clients, the new update is welcome news indeed!