moby: docker logs -f fails when container rotates log file

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BUG REPORT INFORMATION

Using docker logs -f <containerID> to follow the output logs of a container seems to stop after a while, and sooner if the --log-opt max-size is set to a low value. What we’ve seen in live production systems, is that only the first log-file is properly followed, but the second it rotates, the docker logs -f command stops tracking the file. Maybe a fsnotify is not being triggered correctly?

Steps to reproduce the issue:

1. execute the following command to execute a docker container with a small max-size:

   docker run -d --log-driver=json-file --log-opt max-size=1k alpine /bin/ash -c 'while true; do echo "hit CTRL+C to exit"; sleep 1; done'
   

2. Follow the container logs using the follow command:

   docker logs -f <containerID>
   

Describe the results you received: The log output stops after around 10-12 lines and never pick up again, even though the container keeps echoing.

Describe the results you expected: The logs should either keep going or stop (and close the stream) after the json-file was rotated.

Additional information you deem important (e.g. issue happens only occasionally):

This has been observed on both Docker 1.12.6 in Amazon ECS and locally running the version described below using docker version/info.

Output of docker version:

Client:
 Version:      17.03.0-ce
 API version:  1.26
 Go version:   go1.7.5
 Git commit:   60ccb22
 Built:        Thu Feb 23 10:40:59 2017
 OS/Arch:      darwin/amd64

Server:
 Version:      17.03.0-ce
 API version:  1.26 (minimum version 1.12)
 Go version:   go1.7.5
 Git commit:   3a232c8
 Built:        Tue Feb 28 07:52:04 2017
 OS/Arch:      linux/amd64
 Experimental: true

Output of docker info:

Containers: 6
 Running: 0
 Paused: 0
 Stopped: 6
Images: 101
Server Version: 17.03.0-ce
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 ipvlan macvlan null overlay
Swarm: inactive
Runtimes: runc
Default Runtime: runc
Init Binary: docker-init
containerd version: 977c511eda0925a723debdc94d09459af49d082a
runc version: a01dafd48bc1c7cc12bdb01206f9fea7dd6feb70
init version: 949e6fa
Security Options:
 seccomp
  Profile: default
Kernel Version: 4.9.12-moby
Operating System: Alpine Linux v3.5
OSType: linux
Architecture: x86_64
CPUs: 2
Total Memory: 1.952 GiB
Name: moby
ID: TP72:QUAN:KOBL:NK7N:LTOZ:6NRW:NQPN:GH7K:HZD6:QDDE:GSZJ:GSQU
Docker Root Dir: /var/lib/docker
Debug Mode (client): false
Debug Mode (server): true
 File Descriptors: 17
 Goroutines: 28
 System Time: 2017-03-23T13:07:49.418835015Z
 EventsListeners: 1
No Proxy: *.local, 169.254/16
Username: trustpilotdockerhub
Registry: https://index.docker.io/v1/
Experimental: true
Insecure Registries:
 127.0.0.0/8
Live Restore Enabled: false

Additional environment details (AWS, VirtualBox, physical, etc.): Docker for Mac and AWS ECS