Jiajun, Thanks for answering!

I could not find any doc about "Helix supports changing the partition list".

Bootstrap a partition replica can be done by reading off other existing
partitions, as long as the new partition replica knows its own partition
index.

Basically in my design, all machines follow the same Kafka topic, but they
may have progressed to different Kafka offsets. When data moves, they need
to resume from the original offsets.
It's hard to track different offsets for many moving partitions. Is there
any way to put some meta data, such as the Kafka offsets, to the moving
partition?

Chris

On Thu, May 24, 2018 at 3:24 PM, Wang Jiajun <[EMAIL PROTECTED]> wrote: