Hello Rajesh,
There's a ton which could go wrong, firstly - we're not the database, so
you should explain how you use akka to persist these.
* do you mean you send 20k messages, and persist each one then?
* are database writes failing or are messages not delivered?
* who does the db writes? Do
Oh and answering the question in the thread's title.
Akka message sends guarantee *at-most-once-delivery*, because the network
is a dangerous place.
We provide *at-least-once-delivery* via this trait
http://doc.akka.io/docs/akka/snapshot/scala/persistence.html#at-least-once-delivery
but please
