I need to plan a Blogging Platform on Sharepoint which will have support for more than 40,000 blog sites. The users will come and create blog for themselves.
I checked here for capacity planning and the limits : SharePoint Server 2010 capacity management: Software boundaries and limits
Since a site collection can support 250,000 sites, I thought to keep Site collection as top level container and create the blogs as sites and sub-sites under root-web (such that no of sites at a level is <2000).
Later I saw that the max Content DB size is 200 GB which means I only have ~5MB for each blog ( 200GB/40000). This is too less for a blog as the blogger will also upload images while creating blog posts. I need at least 50MB for each blog and want to increase it on demand.
I am thinking to have multiple site collections but it will be difficult to manage users, branding, masterpage, CSS, navigation etc across the site collections. Also, I can't think of how to route a user to new site collection to create blog when 200 GB limit is crossed.
Any ideas for an alternate solution?
Also, I see that we can go up to 4TB of content DB in some special cases. Does anybody have experience with that?