gracefull failover: Rebalance exited with reason {buckets_shutdown_wait_failed

Rebalance exited with reason {buckets_shutdown_wait_failed,

                              [{'ns_1@172.23.96.14',

                                {'EXIT',

                                 {old_buckets_shutdown_wait_failed,

                                  ["bucket-1"]}}}]}

ns_orchestrator 002	ns_1@172.23.96.11	7:17:19 AM Thu Apr 28, 2016

Failed to wait deletion of some buckets on some nodes: [{'ns_1@172.23.96.14',

                                                         {'EXIT',

                                                          {old_buckets_shutdown_wait_failed,

                                                           ["bucket-1"]}}}]

ns_rebalancer 000	ns_1@172.23.96.11	7:17:19 AM Thu Apr 28, 2016

Starting rebalance, KeepNodes = ['ns_1@172.23.96.11','ns_1@172.23.96.12',

                                 'ns_1@172.23.96.13','ns_1@172.23.96.14'], EjectNodes = [], Failed over and being ejected nodes = []; no delta recovery nodes

ns_orchestrator 004	ns_1@172.23.96.11	7:16:59 AM Thu Apr 28, 2016

Shutting down bucket "bucket-1" on 'ns_1@172.23.96.14' for deletion	ns_memcached 000	ns_1@172.23.96.14	7:16:58 AM Thu Apr 28, 2016

Failed over 'ns_1@172.23.96.14': ok	ns_rebalancer 000	ns_1@172.23.96.11	7:16:57 AM Thu Apr 28, 2016

Starting failing over 'ns_1@172.23.96.14'	ns_rebalancer 000	ns_1@172.23.96.11	7:16:57 AM Thu Apr 28, 2016

Bucket "bucket-1" rebalance does not seem to be swap rebalance	ns_vbucket_mover 000	ns_1@172.23.96.11	7:16:45 AM Thu Apr 28, 2016

Starting vbucket moves for graceful failover of 'ns_1@172.23.96.14'	ns_rebalancer 000	ns_1@172.23.96.11	7:16:45 AM Thu Apr 28, 2016

User-triggered compaction of bucket `bucket-1` completed.	compaction_new_daemon 000	ns_1@172.23.96.14	6:53:31 AM Thu Apr 28, 2016

User-triggered compaction of bucket `bucket-1` completed.	compaction_new_daemon 000	ns_1@172.23.96.13	6:53:28 AM Thu Apr 28, 2016

User-triggered compaction of bucket `bucket-1` completed.	compaction_new_daemon 000	ns_1@172.23.96.12	6:53:06 AM Thu Apr 28, 2016

User-triggered compaction of bucket `bucket-1` completed.	compaction_new_daemon 000	ns_1@172.23.96.11	6:52:59 AM Thu Apr 28, 2016

Enabled auto-failover with timeout 120	auto_failover 000	ns_1@172.23.96.11	5:52:35 AM Thu Apr 28, 2016