我已经设置了 CoreOS 但在构建 Docker 时遇到了问题，我不断收到错误，例如：
$ docker run -t -i ubuntu cat /etc/issue
Unable to find image 'ubuntu:latest' locally
latest: Pulling from library/ubuntu
2027caa30175: Verifying Checksum
1a094f2972de: Verifying Checksum
c3eb196f68a8: Already exists
6dba05475398: Already exists
Pulling repository docker.io/library/ubuntu
ab035c88d533: Error pulling image (latest) from docker.io/library/ubuntu, HTTP code 400
808ef855e5b6: Error pulling dependent layers
Error pulling image (latest) from docker.io/library/ubuntu, HTTP code 400
图像正在下载，如图所示
$ docker images -a
REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE
<none> <none> 6dba05475398 24 hours ago 187.9 MB
<none> <none> c3eb196f68a8 24 hours ago 187.7 MB
<none> <none> 35010290964c 9 days ago 133.8 MB
<none> <none> 83bebb94b912 10 weeks ago 133.8 MB
<none> <none> 214e24157b0e 10 weeks ago 133.8 MB
<none> <none> 0bb88100af75 10 weeks ago 133.8 MB
<none> <none> 00b63bcb4ba1 10 weeks ago 133.8 MB
<none> <none> 7e659f5d2aed 10 weeks ago 133.8 MB
<none> <none> 09f7efa54276 10 weeks ago 133.8 MB
<none> <none> 1bcdd78eb3fe 10 weeks ago 125.1 MB
<none> <none> c0d285f6f7a9 10 weeks ago 125.1 MB
<none> <none> d06eec9797c5 10 weeks ago 125.1 MB
<none> <none> 73d9bbce7109 10 weeks ago 125.1 MB
<none> <none> 812c356ae3d1 10 weeks ago 125.1 MB
<none> <none> efb8479c8773 10 weeks ago 125.1 MB
<none> <none> 0b9110ffe91d 10 weeks ago 125.1 MB
这是 docker 日志
$ sudo journalctl -u docker
Mar 19 23:53:30 ded140668.iceserver.net systemd[1]: Started Docker Application Container Engine.
Mar 19 23:53:30 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:53:30.674427729Z" level=info msg="Option DefaultDriver: bridge"
Mar 19 23:53:30 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:53:30.674454736Z" level=info msg="Option DefaultNetwork: bridge"
Mar 19 23:53:30 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:53:30.676393234Z" level=info msg="Firewalld running: false"
Mar 19 23:53:30 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:53:30.752600346Z" level=info msg="Loading containers: start."
Mar 19 23:53:30 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:53:30.752698477Z" level=info msg="Loading containers: done."
Mar 19 23:53:30 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:53:30.752710132Z" level=info msg="Daemon has completed initialization"
Mar 19 23:53:30 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:53:30.752718671Z" level=info msg="Docker daemon" commit=cedd534-dirty execdriver=native-0.2 graph
Mar 19 23:53:30 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:53:30.752743252Z" level=info msg="Listening for HTTP on fd ()"
Mar 19 23:53:34 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:53:34.817525728Z" level=info msg="GET /v1.20/containers/json"
Mar 19 23:53:42 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:53:42.262694351Z" level=info msg="POST /v1.20/images/create?fromImage=ubuntu%3Alatest"
Mar 19 23:53:56 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:53:56.588011328Z" level=error msg="filesystem layer verification failed for digest sha256:a3ed95c
Mar 19 23:53:56 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:53:56.588075662Z" level=error msg="filesystem layer verification failed for digest sha256:2ff1bbb
Mar 19 23:53:56 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:53:56.594750444Z" level=error msg="error copying from layer download progress reader: download ca
Mar 19 23:54:14 ded140668.iceserver.net systemd[1]: Started Docker Application Container Engine.
Mar 19 23:54:18 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:54:18.320407269Z" level=info msg="POST /v1.20/images/create?fromImage=ubuntu%3Alatest"
Mar 19 23:54:32 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:54:32.573946778Z" level=error msg="filesystem layer verification failed for digest sha256:a3ed95c
Mar 19 23:54:32 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:54:32.574010264Z" level=error msg="filesystem layer verification failed for digest sha256:933ae24
Mar 19 23:54:32 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:54:32.574039811Z" level=error msg="filesystem layer verification failed for digest sha256:2ff1bbb
Mar 19 23:54:32 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:54:32.574111690Z" level=error msg="error copying from layer download progress reader: download ca
Mar 19 23:55:14 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:55:14.864768733Z" level=info msg="POST /v1.20/images/create?fromImage=ubuntu%3Alatest"
Mar 19 23:55:28 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:55:28.868636117Z" level=error msg="filesystem layer verification failed for digest sha256:a3ed95c
Mar 19 23:55:28 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:55:28.868765007Z" level=error msg="filesystem layer verification failed for digest sha256:933ae24
Mar 19 23:55:28 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:55:28.868817133Z" level=error msg="filesystem layer verification failed for digest sha256:2ff1bbb
Mar 19 23:55:28 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:55:28.868918287Z" level=error msg="error copying from layer download progress reader: download ca
Mar 19 23:58:58 ded140668.iceserver.net systemd[1]: Stopping Docker Application Container Engine...
Mar 19 23:58:58 ded140668.iceserver.net dockerd[1231]: time="2016-03-19T23:58:58.342154923Z" level=info msg="Processing signal 'terminated'"
Mar 19 23:58:58 ded140668.iceserver.net systemd[1]: Stopped Docker Application Container Engine.
Mar 19 23:59:31 ded140668.iceserver.net systemd[1]: Started Docker Application Container Engine.
Mar 19 23:59:31 ded140668.iceserver.net dockerd[1350]: time="2016-03-19T23:59:31.882882761Z" level=info msg="Option DefaultDriver: bridge"
Mar 19 23:59:31 ded140668.iceserver.net dockerd[1350]: time="2016-03-19T23:59:31.882909462Z" level=info msg="Option DefaultNetwork: bridge"
Mar 19 23:59:31 ded140668.iceserver.net dockerd[1350]: time="2016-03-19T23:59:31.884604837Z" level=info msg="Firewalld running: false"
Mar 19 23:59:31 ded140668.iceserver.net dockerd[1350]: time="2016-03-19T23:59:31.951600473Z" level=info msg="Loading containers: start."
Mar 19 23:59:31 ded140668.iceserver.net dockerd[1350]: time="2016-03-19T23:59:31.951704928Z" level=info msg="Loading containers: done."
Mar 19 23:59:31 ded140668.iceserver.net dockerd[1350]: time="2016-03-19T23:59:31.951714625Z" level=info msg="Daemon has completed initialization"
Mar 19 23:59:31 ded140668.iceserver.net dockerd[1350]: time="2016-03-19T23:59:31.951723738Z" level=info msg="Docker daemon" commit=cedd534-dirty execdriver=native-0.2 graph
Mar 19 23:59:31 ded140668.iceserver.net dockerd[1350]: time="2016-03-19T23:59:31.951749082Z" level=info msg="Listening for HTTP on fd ()"
Mar 19 23:59:49 ded140668.iceserver.net dockerd[1350]: time="2016-03-19T23:59:49.314516845Z" level=info msg="GET /v1.20/images/json"
Mar 19 23:59:49 ded140668.iceserver.net dockerd[1350]: time="2016-03-19T23:59:49.335452926Z" level=info msg="DELETE /v1.20/images/c3eb196f68a8"
Mar 19 23:59:49 ded140668.iceserver.net dockerd[1350]: time="2016-03-19T23:59:49.496175275Z" level=info msg="DELETE /v1.20/images/87bd195bb945"
Mar 20 00:00:00 ded140668.iceserver.net dockerd[1350]: time="2016-03-20T00:00:00.962219014Z" level=info msg="GET /v1.20/containers/json"
Mar 20 00:00:24 ded140668.iceserver.net dockerd[1350]: time="2016-03-20T00:00:24.280787541Z" level=info msg="POST /v1.20/images/create?fromImage=ubuntu%3Alatest"
在不同的机器、不同的网络位置上执行相同的操作，效果很好。
没有代理。
这是我的 CoreOS 设置的问题吗？