That format looks a little different that what it was expecting when reading from a log file. Yours has the original syslog pri and some additional number at the start. This is what it expects.
The good news is that you can edit that dissect pattern in your Filebeat install and it should work.
I think the right tokenizer for the format your logs are in would be
Apache, Apache Lucene, Apache Hadoop, Hadoop, HDFS and the yellow elephant
logo are trademarks of the
Apache Software Foundation
in the United States and/or other countries.