Graylog 0msg/s ouput

Hi guys,
When I delete journal message because my graylog cluster is full Process buffer.But when I restart our graylog cluster, graylog hadn’t pushed message to elasticsearch cluster anymore.
I checked logs, resources and connections between graylog and elasticsearch cluster are OK.
Graylog version 2.3.1, elasticsearch version 5.6.


Here is my capture screen.
Thanks.

You have to stop Graylog before deleting the journal files.