Docker checkpoint is restarting the process instead of saving the state.

[chenchix]

Once docker start is called, instead of restore the process, it starts from the beggining.

How to test:

docker run -d --name looper2 busybox \
>          /bin/sh -c 'i=0; while true; do echo $i; i=$(expr $i + 1); sleep 1; done'
abe7a20ad9f6842cfe66762c72c6503188cc836ec4c36ea9648638b53b6701cb
docker logs ab
0
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docker checkpoint create  looper2 checkpoint2

docker start --checkpoint=checkpoint2 looper2
docker logs ab
0
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0
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Docker version: Docker version 19.03.8, build afacb8b7f0
Criu version: Version: 3.15
Kernel: Linux codillo 5.4.0-050400-generic #201911242031 SMP Mon Nov 25 01:35:10 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

Distributor ID: Ubuntu
Description: Ubuntu 20.04.1 LTS
Release: 20.04
Codename: focal

[niernzc]

I've met the same problem. My machine was Centos7 with Kernel 3.10
Docker Version

Client: Docker Engine - Community
 Version:           20.10.2
 API version:       1.41
 Go version:        go1.13.15
 Git commit:        2291f61
 Built:             Mon Dec 28 16:17:48 2020
 OS/Arch:           linux/amd64
 Context:           default
 Experimental:      true

Server: Docker Engine - Community
 Engine:
  Version:          20.10.2
  API version:      1.41 (minimum version 1.12)
  Go version:       go1.13.15
  Git commit:       8891c58
  Built:            Mon Dec 28 16:16:13 2020
  OS/Arch:          linux/amd64
  Experimental:     true
 containerd:
  Version:          1.4.3
  GitCommit:        269548fa27e0089a8b8278fc4fc781d7f65a939b
 runc:
  Version:          1.0.0-rc92
  GitCommit:        ff819c7e9184c13b7c2607fe6c30ae19403a7aff
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0

then I solved this problem by upgrading the kernel to 5.10, and pulling the latest code from Git and recompile and install Containerd and Runc
Now Docker Version:

Client: Docker Engine - Community
 Version:           20.10.2
 API version:       1.41
 Go version:        go1.13.15
 Git commit:        2291f61
 Built:             Mon Dec 28 16:17:48 2020
 OS/Arch:           linux/amd64
 Context:           default
 Experimental:      true

Server: Docker Engine - Community
 Engine:
  Version:          20.10.2
  API version:      1.41 (minimum version 1.12)
  Go version:       go1.13.15
  Git commit:       8891c58
  Built:            Mon Dec 28 16:16:13 2020
  OS/Arch:          linux/amd64
  Experimental:     true
 containerd:
  Version:          v1.4.0-2324-g0ec47b3
  GitCommit:        0ec47b33488d295785a9d1702c9552a491802898
 runc:
  Version:          1.0.0-rc92+dev
  GitCommit:        cf6c074115d00c932ef01dedb3e13ba8b8f964c3
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0

NOW My Problem is ,What are the specific requirements for Docker C/R?

[DivyanshuSaxena]

Downgrading docker to 19.03 using the static binaries does the trick. Ref: checkpoint-restore/criu#1365