THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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UnderReplicated: A partition in which the isr_set_size is not equal to the replica_set_size (isr_set_size can be bigger or smaller than replica_replication_factor)
AtMinIsr: A partition in which the isr_set_size is equal to the min_isr_size, which also means a partition in which 1 more drop in isr_set_size will lead to at least producer (acks=ALL) failure
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