Hi, the bolt is created and prepared the same way as when the topology is created. You need to recover your map from the DB yourself, in the prepare() method of your bolt. Also note that the spout will keep emitting tuples even when the bolt is dead, so you had better set the topology.max.pending property to keep the buffers from filling up and the tuple timeout to accomodate the time your bolt takes to recover. Hope it helps, Martin
po 7. 9. 2015 v 8:59 odesÃlatel Calvin Iyer <[email protected]> napsal: > Hi, > > I have a query about what happens if a storm bolt dies. My current > topology is such that I have a Kafka spout that gives out records which are > counted in a storm bolt and stored in a hashmap in the same bolt and emits > the aggregated map to another bolt every 5 mins to persist it to a > database. Now supposing that the bolt dies while having data in the map and > the task gets reassigned to another worker does the map also get recreated > or does it use the last snapshot of the map before it failed ? > > Thanks, > Calvin >
