Concurrent Create GSI INDEX with Bucket flush operation => select * from system:indexes errors with Failed to load indexes Keyspace default - cause: all nodes failed to respond

./testrunner -i b/resources/dev-6-nodes-xdcr_n1ql_2i.ini -t 2i.recovery_2i.SecondaryIndexingRecoveryTests.test_couchbase_bucket_flush,nodes_init=5,nodes_in=1,before=,in_between=create_index,after=drop_index,groups=simple,dataset=default,doc-per-day=10,services_init=n1ql:kv-kv-kv-index-index,doc-per-day=40,skip_cleanup=True

1. Create 5 node cluster (1:n1ql,kv 2:kv 3:kv 4:index 5:index
2. Create default bucket with 80K items - employee data set
3. Create primary index using views, 5 gsi indexes - wait till they are online
4. Create 2 GSI indexes on each nodes
5. Flush the bucket
6. Wait till indexes are online

Step 4, 5, 6 happens in parallel

We receive the following response while checking the cluster is online

by doing select * from system:indexes

ERROR:{u'status': u'errors', u'errors': [

{u'msg': u'System datastore error - cause: Failed to load indexes for keyspace default - cause: Failed to load indexes Keyspace default - cause: all nodes failed to respond', u'code': 11000}

], u'results': [], u'metrics':

{u'elapsedTime': u'57.828958ms', u'executionTime': u'57.736728ms', u'resultSize': 0, u'resultCount': 0, u'errorCount': 1}

, u'requestID': u'fa4668e4-7d26-469f-b6c8-de66e8ccf463', u'signature': {u'': u''}}