Why "warning msg=unable to pin image" is seen while creating a docker service in Red Hat Enterprise Linux 7 with docker-1.13.1-63.git94f4240.el7.x86_64 ?

Issue

• Why "warning msg=unable to pin image" is seen while creating a docker service in Red Hat Enterprise Linux 7 with docker-1.13.1-63.git94f4240.el7.x86_64 ?

[root@d1 ~]# docker service create --replicas 1 --mount type=volume,src=foo,dst=/test --restart-condition none --name test busybox  ls /test/
unable to pin image busybox to digest: unknown: Not Found
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• Why service creation fails with the message "unable to pin image" with " no basic auth credentials" ?

[root@d1 ~]# docker service create --with-registry-auth --replicas 1 --mount type=volume,src=foo,dst=/test --restart-condition none --name test 192.168.0.11:5000/dockertestimage  ls /test/
unable to pin image 192.168.0.11:5000/dockertestimage to digest: Head http://192.168.0.11:5000/v2/dockertestimage/manifests/latest: no basic auth credentials
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