How WhatsApp moved 1.5B users across data centers

For the last 3 years WhatsApp was working on integration with Facebook infrastructure. A big part of work there was data migration to Facebook data centers. This presentation is about the journey we went through to get there, challenges we faced and solutions we came up with.

  • How to call into C++ from Erlang?
  • How to copy data with no effect on production traffic?
  • How to deal with cross-DC network cuts, server restarts, hardware losses, etc?
  • How to switch users from one DC to another?


Share knowledge, experience, and best practices.


Experienced engineers and architects.