Logstash can not write date into elasticsearch after activating elastic security

[TimV (Tim Vernum)]

@PolterFox

elasticsearch {
    index => "log-%{+YYYY.MM.dd}"
    id => "elasticsearch_logging_receiver"
    user => logstash_internal
    password => *******
}

You need to string-quote those values:

elasticsearch {
    index => "log-%{+YYYY.MM.dd}"
    id => "elasticsearch_logging_receiver"
    user => "logstash_internal"
    password => "*******"
}