My logstash got a hashed value hostname

The feedback message is
{ "message":"xxx",

the host is a hashed value
Is there any way that I can get the ip address or domain name in the host field?
How can I configure it?

Please tell us more about your setup. Are you by any chance running Logstash in a Docker container?

Yes. I am running logstash in a docker container. And I've found the way to add a customized hostname.
FYI, just run the container with docker run --hostname=yourhostname logstash