# Docker not running on CentOS 7 rt Kernel

**URL:** <https://forums.docker.com/t/docker-not-running-on-centos-7-rt-kernel/27262>\
**Category:** General\
**Created:** [January 18, 2017, 9:43am UTC](https://forums.docker.com/t/docker-not-running-on-centos-7-rt-kernel/27262 "2017-01-18T09:43:39Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![ilatif](https://avatars.discourse-cdn.com/v4/letter/i/4491bb/32.png) [@ilatif](https://forums.docker.com/u/ilatif)\
**Post date:** [January 18, 2017, 9:43am UTC](https://forums.docker.com/t/docker-not-running-on-centos-7-rt-kernel/27262/1 "2017-01-18T09:43:39Z")

</div>

Hi,

First of all I would like to inform you guys that I am a newbie in docker and linux so please forgive my stupid questions or remarks if any.

I have successfully installed docker on CentOS 7 using the described in here [CentOS | Docker Docs](https://docs.docker.com/engine/installation/linux/centos/).  
Please note that I am using RT kernel 3.10.104-rt116.

But when I try to run the hello-world application in docker, I get the following error.  
**_[root@Imran ~]# sudo docker run --rm hello-world_**  
**_Unable to find image ‘hello-world:latest’ locally_**  
**_latest: Pulling from library/hello-world_**  
**_78445dd45222: Extracting 971 B/971 B_**  
**_docker: failed to register layer: devmapper: Error mounting ‘/dev/mapper/docker-253:0-140399561-7005371d5ef5c995d9af5290e36a2507372124823fdce8c673aa569d1fc5c2e9’ on ‘/var/lib/docker/devicemapper/mnt/7005371d5ef5c995d9af5290e36a2507372124823fdce8c673aa569d1fc5c2e9’: invalid argument._**  
**_See ‘docker run --help’._**

my docker version is the latest one:  
docker -v  
Docker version 1.13.0-rc7, build 48a9e53

Does anyone have any idea so as to why is this error occurring?

As a side help I came across the check-config.sh script from docker webpage and when I run it I see the following output.

Generally Necessary:

- cgroup hierarchy: properly mounted [/sys/fs/cgroup]
- CONFIG\_NAMESPACES: enabled
- CONFIG\_NET\_NS: enabled
- CONFIG\_PID\_NS: enabled
- CONFIG\_IPC\_NS: enabled
- CONFIG\_UTS\_NS: enabled
- CONFIG\_CGROUPS: enabled
- CONFIG\_CGROUP\_CPUACCT: enabled
- CONFIG\_CGROUP\_DEVICE: enabled
- CONFIG\_CGROUP\_FREEZER: enabled
- CONFIG\_CGROUP\_SCHED: enabled
- CONFIG\_CPUSETS: enabled
- CONFIG\_MEMCG: enabled
- CONFIG\_KEYS: enabled
- CONFIG\_VETH: enabled (as module)
- CONFIG\_BRIDGE: enabled (as module)
- CONFIG\_BRIDGE\_NETFILTER: enabled
- CONFIG\_NF\_NAT\_IPV4: enabled (as module)
- CONFIG\_IP\_NF\_FILTER: enabled (as module)
- CONFIG\_IP\_NF\_TARGET\_MASQUERADE: enabled (as module)
- CONFIG\_NETFILTER\_XT\_MATCH\_ADDRTYPE: enabled (as module)
- CONFIG\_NETFILTER\_XT\_MATCH\_CONNTRACK: enabled (as module)
- CONFIG\_NETFILTER\_XT\_MATCH\_IPVS: enabled (as module)
- CONFIG\_IP\_NF\_NAT: missing
- CONFIG\_NF\_NAT: enabled (as module)
- CONFIG\_NF\_NAT\_NEEDED: enabled
- CONFIG\_POSIX\_MQUEUE: enabled
- CONFIG\_DEVPTS\_MULTIPLE\_INSTANCES: enabled

Optional Features:

- CONFIG\_USER\_NS: missing  
(RHEL7/CentOS7: User namespaces disabled; add ‘user\_namespace.enable=1’ to boot command line)
- CONFIG\_SECCOMP: enabled
- CONFIG\_CGROUP\_PIDS: missing
- CONFIG\_MEMCG\_SWAP: enabled
- CONFIG\_MEMCG\_SWAP\_ENABLED: enabled
- CONFIG\_MEMCG\_KMEM: enabled
- CONFIG\_RESOURCE\_COUNTERS: enabled
- CONFIG\_BLK\_CGROUP: enabled
- CONFIG\_BLK\_DEV\_THROTTLING: enabled
- CONFIG\_IOSCHED\_CFQ: enabled
- CONFIG\_CFQ\_GROUP\_IOSCHED: enabled
- CONFIG\_CGROUP\_PERF: enabled
- CONFIG\_CGROUP\_HUGETLB: enabled
- CONFIG\_NET\_CLS\_CGROUP: enabled
- CONFIG\_NETPRIO\_CGROUP: enabled (as module)
- CONFIG\_CFS\_BANDWIDTH: enabled
- CONFIG\_FAIR\_GROUP\_SCHED: enabled
- CONFIG\_RT\_GROUP\_SCHED: missing
- CONFIG\_IP\_VS: enabled (as module)
- CONFIG\_IP\_VS\_NFCT: enabled
- CONFIG\_IP\_VS\_RR: enabled (as module)
- CONFIG\_EXT3\_FS: missing
- CONFIG\_EXT3\_FS\_XATTR: missing
- CONFIG\_EXT3\_FS\_POSIX\_ACL: missing
- CONFIG\_EXT3\_FS\_SECURITY: missing  
(enable these ext3 configs if you are using ext3 as backing filesystem)
- CONFIG\_EXT4\_FS: enabled (as module)
- CONFIG\_EXT4\_FS\_POSIX\_ACL: enabled
- CONFIG\_EXT4\_FS\_SECURITY: enabled
- Network Drivers:
  - “overlay”:
    - CONFIG\_VXLAN: enabled (as module)  
Optional (for encrypted networks):
      - CONFIG\_CRYPTO: enabled
      - CONFIG\_CRYPTO\_AEAD: enabled
      - CONFIG\_CRYPTO\_GCM: enabled (as module)
      - CONFIG\_CRYPTO\_SEQIV: enabled
      - CONFIG\_CRYPTO\_GHASH: enabled (as module)
      - CONFIG\_XFRM: enabled
      - CONFIG\_XFRM\_USER: enabled
      - CONFIG\_XFRM\_ALGO: enabled
      - CONFIG\_INET\_ESP: enabled (as module)
      - CONFIG\_INET\_XFRM\_MODE\_TRANSPORT: enabled (as module)

  - “ipvlan”:
    - CONFIG\_IPVLAN: missing

  - “macvlan”:
    - CONFIG\_MACVLAN: enabled (as module)
    - CONFIG\_DUMMY: enabled (as module)

  - “ftp,tftp client in container”:
    - CONFIG\_NF\_NAT\_FTP: enabled (as module)
    - CONFIG\_NF\_CONNTRACK\_FTP: enabled (as module)
    - CONFIG\_NF\_NAT\_TFTP: enabled (as module)
    - CONFIG\_NF\_CONNTRACK\_TFTP: enabled (as module)

- Storage Drivers:
  - “aufs”:
    - CONFIG\_AUFS\_FS: missing

  - “btrfs”:
    - CONFIG\_BTRFS\_FS: enabled (as module)
    - CONFIG\_BTRFS\_FS\_POSIX\_ACL: enabled

  - “devicemapper”:
    - CONFIG\_BLK\_DEV\_DM: enabled (as module)
    - CONFIG\_DM\_THIN\_PROVISIONING: enabled (as module)

  - “overlay”:
    - CONFIG\_OVERLAY\_FS: missing

  - “zfs”:
    - /dev/zfs: missing
    - zfs command: missing
    - zpool command: missing

Limits:

- /proc/sys/kernel/keys/root\_maxkeys: 1000000

I see that in necessary config I am missing “CONFIG\_IP\_NF\_NAT” so I have tried to find this option using make menuconfig but I could not find it. I tried to search this issue in open forums but I could not find a solution which works for me.

I shall be really grateful for your help.

Thanks

Regards  
Imran