Recently had a conversation with a customer about how SharePoint 2013 works within a Geographically dispersed environment, and here are the highlights from that conversation.
First thing we need to do is review if we actually need to have a geographically dispersed farm or can we actually use a Central Farm due to improvements that come with SharePoint 2013. Some of these improvements are
1. Optimized Web Pages
2. Improved Client tools like SkyDrive Pro, SharePoint Workspace 2010, and Office Web App Servers
Next I would review if it would be better to improve the WAN thru one of the following manners
1. Improve Network connections
2. Windows services like BranchCache
3. WAN Accelerators
If after all that you still want to create a dispersed environment there are different choices you will have, realize each has it pro’s and con’s and should be considered carefully
1. Regional farms with Shared Service Farm(s)
a. Creating regional farmers and storing Sites/Data based on these regions can provide faster returns times for the people in those locations.
b. Most Service Applications are supported to work across WAN so you can have a single search engine or Metadata database to support all your farms
c. Social is one of the few services that is not supported across WAN connections here are some recommendations
i. A single My Site farm is recommended to insure you can take full advantage of Social features ii. User Profile Service must reside in each Content Farm iii. You can use UPRE to replicate profile data between farms
d. Search while supported across WAN, we do not recommend crawling across the WAN, so you should have each farm crawl itself and use different Search Web Parts to provide the complete result sets to users.
2. Stretched farms
a. Are supported, but requires the following network speeds and latency
i. 1 millisecond latency from SQL server and WFE ii. 1 GB per second bandwidth
3. Database replication
a. Microsoft does not support Database replication using SQL across WAN connections for anything but Disaster Recovery
b. There are 3 rd party companies which have created tools to replicate data across WAN connections. These solutions are supported by those companies, Microsoft support would be best effort for farms with these tools, as well Microsoft or I do not recommend any particular 3 rd party company over the other. With all that said here are two solutions that I found.