-- Unit docker.service has begun starting up.
Nov 18 22:16:41 server dockerd[6351]: time="2018-11-18T22:16:41-07:00" level=warning msg="Running experimental build"
Nov 18 22:16:41 server dockerd[6351]: time="2018-11-18T22:16:41.149758139-07:00" level=info msg="User namespaces: ID ranges will be mapped to subuid/subgid ranges of: lxd:lxd"
Nov 18 22:16:41 server dockerd[6351]: time="2018-11-18T22:16:41.159295190-07:00" level=info msg="systemd-resolved is running, so using resolvconf: /run/systemd/resolve/resolv.conf"
Nov 18 22:16:41 server dockerd[6351]: time="2018-11-18T22:16:41.159453828-07:00" level=info msg="User namespaces: ID ranges will be mapped to subuid/subgid ranges of: lxd:lxd"
Nov 18 22:16:41 server dockerd[6351]: time="2018-11-18T22:16:41.160388092-07:00" level=info msg="parsed scheme: "unix"" module=grpc
Nov 18 22:16:41 server dockerd[6351]: time="2018-11-18T22:16:41.160423687-07:00" level=info msg="scheme "unix" not registered, fallback to default scheme" module=grpc
Nov 18 22:16:41 server dockerd[6351]: time="2018-11-18T22:16:41.160470021-07:00" level=info msg="parsed scheme: "unix"" module=grpc
Nov 18 22:16:41 server dockerd[6351]: time="2018-11-18T22:16:41.160482788-07:00" level=info msg="scheme "unix" not registered, fallback to default scheme" module=grpc
Nov 18 22:16:41 server dockerd[6351]: time="2018-11-18T22:16:41.160560969-07:00" level=info msg="ccResolverWrapper: sending new addresses to cc: [{unix:///run/containerd/containerd.sock 0  <nil>}]" module=grpc
Nov 18 22:16:41 server dockerd[6351]: time="2018-11-18T22:16:41.160601454-07:00" level=info msg="ClientConn switching balancer to "pick_first"" module=grpc
Nov 18 22:16:41 server dockerd[6351]: time="2018-11-18T22:16:41.160588007-07:00" level=info msg="ccResolverWrapper: sending new addresses to cc: [{unix:///run/containerd/containerd.sock 0  <nil>}]" module=grpc
Nov 18 22:16:41 server dockerd[6351]: time="2018-11-18T22:16:41.160697436-07:00" level=info msg="ClientConn switching balancer to "pick_first"" module=grpc
Nov 18 22:16:41 server dockerd[6351]: time="2018-11-18T22:16:41.160743537-07:00" level=info msg="pickfirstBalancer: HandleSubConnStateChange: 0xc4200db9f0, CONNECTING" module=grpc
Nov 18 22:16:41 server dockerd[6351]: time="2018-11-18T22:16:41.160691768-07:00" level=info msg="pickfirstBalancer: HandleSubConnStateChange: 0xc42009a1d0, CONNECTING" module=grpc
Nov 18 22:16:41 server dockerd[6351]: time="2018-11-18T22:16:41.160760682-07:00" level=warning msg="Unable to locate plugin: devicemapper, retrying in 1s"
Nov 18 22:16:41 server dockerd[6351]: time="2018-11-18T22:16:41.160773855-07:00" level=info msg="blockingPicker: the picked transport is not ready, loop back to repick" module=grpc
Nov 18 22:16:41 server dockerd[6351]: time="2018-11-18T22:16:41.160922445-07:00" level=info msg="pickfirstBalancer: HandleSubConnStateChange: 0xc42009a1d0, READY" module=grpc
Nov 18 22:16:41 server dockerd[6351]: time="2018-11-18T22:16:41.160999752-07:00" level=info msg="pickfirstBalancer: HandleSubConnStateChange: 0xc4200db9f0, READY" module=grpc
Nov 18 22:16:42 server dockerd[6351]: time="2018-11-18T22:16:42.161035546-07:00" level=warning msg="Unable to locate plugin: devicemapper, retrying in 2s"
Nov 18 22:16:44 server dockerd[6351]: time="2018-11-18T22:16:44.161383150-07:00" level=warning msg="Unable to locate plugin: devicemapper, retrying in 4s"
Nov 18 22:16:48 server dockerd[6351]: time="2018-11-18T22:16:48.161695623-07:00" level=warning msg="Unable to locate plugin: devicemapper, retrying in 8s"

{
    "userns-remap": "lxd",
    "userland-proxy": false,
    "storage-driver": "devicemapper",
    "storage-opts": [
      "dm.thinpooldev=/dev/mapper/docker-thinpool",
      "dm.use_deferred_removal=true",
      "dm.use_deferred_deletion=true"
    ]
}

Linux server 4.15.0-36-generic #39-Ubuntu SMP Mon Sep 24 16:19:09 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux