Unable to update license

Elastic Stack Elasticsearch
1

Marvel is telling me that my license expired. I followed the instructions to register for a basic license and was provided a .json file. However, when I PUT it, I get a transport serialization exception:

curl -XPUT <ip address>:9200/_license?pretty -d @<downloaded license file.json>
{
  "error" : {
    "root_cause" : [ {
      "type" : "transport_serialization_exception",
      "reason" : "Failed to deserialize response of type [org.elasticsearch.license.plugin.action.put.PutLicenseResponse]"
    } ],
    "type" : "transport_serialization_exception",
    "reason" : "Failed to deserialize response of type [org.elasticsearch.license.plugin.action.put.PutLicenseResponse]",
    "caused_by" : {
      "type" : "array_index_out_of_bounds_exception",
      "reason" : "1"
    }
  },
  "status" : 500
}

The error implies it's looking at an array, but license file doesn't contain any arrays.

The cluster is running ElasticSearch 2.1.1

2

For whatever reason, applying the license to a data node, rather than a client node, succeeded.