I have a problem in following situation:

I have 2 separate Wordpress 3.3.1 instances, main at domain.com and one of them (which consists of simple Q&A type site) is available from subdomain forum.domain.com. Now I have to merge them into one instance - to be able to share plugins, theme and posts (<-- that's important).

At this moment, forum.domain.com points to that second instance. I can quite easily get rid of it just by creating post categories for questions and displaying them accordingly. But then, my questions will have links like domain.com/category/forum/question-subcategory/question and I want them to be like forum.domain.com/question-subcategory/question. I've seen that there is a WP Subdomains plug-in that does exactly that but it's not compatible with WP 3.3.1. I thought that should be possible with .htaccess rules but this post seems to explain that it's not.

I considered using WP Multi-site feature but as far as I know, separate sites have separate tables in DB, thus they can't share posts (which is needed, as previously said).

Does anybody have any clue how to fix this problem ?

  • Can't vote up but really interested in replies to this! - Thanks – user15070 Apr 11 '12 at 10:10
  • Sites in a multisite instance can interact with eachother. Refer to these functions: get_current_blog_id(), switch_to_blog() and restore_current_blog() – Tom J Nowell Apr 11 '12 at 10:49

Well, thanks for hints but finally, I had to abandon the idea of subdomain due to lack of working solution for this. I made separate categories for questions and used some hooks to display&operate on them properly. Thanks to the Custom Permalinks plugin, I now have domain.com (main blog) and domain.com/forum/ (Q&A), and the latter seems to be different site - with different headers, sidebars, logic, etc. from user's point of view (it's all on one instance, of course).


I too struggled immensely trying to use subdomains for categories on my wordpress site. I tried a variety of plugins that were very buggy and eventually attempted writing my own. I kept running into additional problems left and right. Frequently I'd add new plugins that didn't function properly with the unconventional subdomain setup and I ultimately gave up on trying to make this work.

The only "solution" that I think might end up working is a wordpress multisite where each site holds posts for a given category then all sites are aggregated on a master site. This introduces another big heap of chores but I think it would actually function properly. It'd just be a pain in the neck.

Anyway, to all that read this post, if you do find a solution that works for you, please do chime in and let us know.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.