Here is my request:
POST /_bulk { \"index\" : { \"_index\" : \"test\", \"_type\" : \"type1\", \"_id\" : \"1\" } } {\"firstname\":\"first_name1\",\"lastname\"
As Samyak says in his comment, "don't repeat yourself". This syntax is tidier.
post /test/_type/_bulk { "index": {}} {"firstname":"first_name1","lastname":"last_name1"} { "index": { }} { "name": "Test2", "data": "This is my test data2" }