Reindexing Elasticsearch with Logstash 2.0

logstash.conf

input {
  elasticsearch {
    hosts => [ "HOSTNAME_HERE" ]
    port => "9200"
    index => "INDEXNAME_HERE"
    size => 1000
    scroll => "5m"
    docinfo => true
    scan => true
  }
}

output {
  elasticsearch {
    hosts => [ "HOSTNAME_HERE" ]
    index => "%{[@metadata][_index]}"
    document_type => "%{[@metadata][_type]}"
    document_id => "%{[@metadata][_id]}"
  }
  stdout {
    codec => "dots"
  }
}