Share a SESSION across multiple servers with different domains [duplicate]
Two options from the top of my head that you can explore:
Set all servers the same path for saving its session data, seesession.save_path directive. That location could be a NFS shareor a NAS location that all your servers could access.
The other option is to implement a database session handler, sothe session data could be shared among allyour servers accessing the same database server. So take a look at PHP docsfor custom session handlers.