I have to change my site domain. Is it possible to change the forum domain from www.forum.com to forum.site.com (move from main domain to subdomain) with saving index? Do you recommend this? Does XenForo have addon for that? Thank you!
It's the same process of moving any site to a sub domain. Just remember to update your license information and set up 301 redirects so you do not lose out on any traffic or search engine ranking positions.