My logstash got a hashed value hostname

Elastic Stack Logstash
1

The feedback message is
{ "message":"xxx",
"host":"da30faafb1s4e2d2"
}

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?

2

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

3

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
Thanks