As part of the cross-wiki search results new functionality, it appears that the deployment/switchover of the new centralized document id will be complicated and we'll need to figure it out.

Erik's deployment notes: https://wikitech.wikimedia.org/wiki/User:EBernhardson/MultiProjectIndicesDeployment

• deployment is also dependent on the CirrusSearch config
• two main suggested deployment methods (so far):
  • route everything to cluster1, set up cluster2 on the new schema, route everything to cluster2, set up cluster1 on new schema, route to both again
  • set up cluster1 with new schema, route info to both; each cluster interprets doc id info differently (old style vs new style); when cluster1 is working fine, make the switch over to cluster 2
• in every case, converting the old id style to the new is going to be a big step to take