Cannot -H to the host adb server

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Hello, I am trying to the real-device version of the docker image, but when I try to "adb -H " to the host machine adb server, following error shows:


My host machine is Linux and my docker info is listed below, the real android device is connected to this host machine and the host machine adb cmd can recognise the device as well.
And I try to access the Host Linux machine from a PC (my development machine).
```
Containers: 23
Running: 1
Paused: 0
Stopped: 22
Images: 109
Server Version: 18.09.7
Storage Driver: overlay2
Backing Filesystem: extfs
Supports d_type: true
Native Overlay Diff: true
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins:
Volume: local
Network: bridge host macvlan null overlay
Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
Swarm: inactive
Runtimes: nvidia runc
Default Runtime: runc
Init Binary: docker-init
containerd version: xxxxx
runc version: 425e105d5a03fabd737a126ad93d62a9eeede87f
init version: fec3683
Security Options:
apparmor
seccomp
Profile: default
Kernel Version: 4.15.0-54-generic
Operating System: Ubuntu 16.04.6 LTS
OSType: linux
Architecture: x86_64
CPUs: 12
Total Memory: 15.61GiB
Name: xxxxxxxxxx
ID: xxxxxxx
Docker Root Dir: xxxx
Debug Mode (client): false
Debug Mode (server): false
Registry: https://index.docker.io/v1/
Labels:
Experimental: false
Insecure Registries:
127.0.0.0/8
Live Restore Enabled: false
Product License: Community Engine

WARNING: No swap limit support

```

I have used the x86 simulator version docker image, it works fine when I access the emulator from a remote PC, and the virtual device show up in my Android Studio. But why it blocks the real device docker?