[BP 5.5.6] Unable to create replica index

Build : 6.5.0-3100

Steps :
1. Setup a 1-node cluster with kv, query and index services
2. Install beer-sample dataset
3. Add an index node to this cluster.
4. Create an index like :
create index idx1 on `beer-sample`(name,city) with

This index creation fails with the error :
[
{
"code": 5000,
"msg": "GSI CreateIndex() - cause: Fails to create index. There are not enough indexer nodes to create index with replica count of 1. Some indexer nodes may be marked as excluded.",
"query": "create index idx1 on `beer-sample`(name,city) with

"
}
]

There are some errors in the query log like :
2019-05-01T14:12:26.549-07:00 [Error] updateIndexerList(): Cannot locate cluster node.