Would it hurt SEO for a sitemap to be hosted on a different domain if you 301 direct to it?

Question

We compute our sitemap periodically with a cron job and store the results in s3.

Can we 301 redirect https://oursite.com/sitemap.xml to the sitemap.xml hosted on s3?

I know that the sitemap spec requires the sitemap to be on the same domain (http://www.sitemaps.org/protocol.html#location). But would a 301 to an off-domain URL be treated by the major search providers as being on the same domain or off of it?

Answer 1

Yes, you can. In short, you have to prove that you own the parent site, and you can do that by including the sitemap's URL from s3 in the robots.txt file of the parent site.

Parent site's robots.txt should get a section like:

# myawesomesite.com/robots.txt

[...]
Sitemap: http://s3.yoursite.com/sitemap.xml

See more in Sitemaps & Cross Submits section of Sitemaps.Org