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By assigning and revoking partitions for the members of the group, the group coordinator can balance the partitions across the members of the group.
The member provides the rebalance timeout to the group coordinator when it joins the group. This is the timeout for the group coordinator waiting for the member to acknowledge that it has adopted the target assignment. If the member does not confirm the target assignment within the rebalance timeout, the group coordinator removes the member from the group.
Member ID
Every member is uniquely identified by the UUID called the member ID. This UUID is generated by the group coordinator and given to the member when it joins the group. It is used in all communication with the group coordinator and must be kept during the entire lifespan of the member.
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