安装Rancher（k3s）踩坑Cgroup问题-摩杜云开发者社区

较新版本的docker desktop使用了cgroupv2,Rancher server的docker镜像，还要考虑历史兼容问题，所以server内置的k3s还不兼容cgroupv2的方式。所以我们需要将,Docker 切换回cgroup v1。

vi /etc/default/grub
添加：
GRUB_CMDLINE_LINUX="systemd.unified_cgroup_hierarchy=0"
更新grub配置,使修改生效
grub2-mkconfig  -o /boot/grub2/grub.cfg
重启服务器

查看Linux cgrougp版本：：

stat -fc %T /sys/fs/cgroup

对于cgroup v2,输出为 cgroup2fs。

对于cgroup v1，输出为tmpfs。

[root@cdss-server2 ~]# docker info
Client:
 Debug Mode: false

Server:
 Containers: 55
  Running: 48
  Paused: 0
  Stopped: 7
 Images: 44
 Server Version: 19.03.12
 Storage Driver: overlay2
  Backing Filesystem: xfs
  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
  Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
 Swarm: inactive
 Runtimes: runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: 7ad184331fa3e55e52b890ea95e65ba581ae3429
 runc version: dc9208a3303feef5b3839f4323d9beb36df0a9dd
 init version: fec3683
 Security Options:
  seccomp
   Profile: default
 Kernel Version: 4.17.11-1.el7.elrepo.x86_64
 Operating System: CentOS Linux 7 (Core)
 OSType: linux
 Architecture: x86_64
 CPUs: 10
 Total Memory: 31.38GiB
 Name: cdss-server2
 ID: FCBD:GFLB:NPQT:3E4Z:QASL:TTWE:S63W:3JPN:7WOO:YTWO:LBSL:3D77
 Docker Root Dir: /home/lib/docker
 Debug Mode: false
 Registry: https://index.docker.io/v1/
 Labels:
 Experimental: false
 Insecure Registries:
  iregistry.baidu-int.com
  registry.baidu.com
  cdss-server1:5000
  127.0.0.0/8
 Live Restore Enabled: false

docker version:

Client: Docker Engine - Community
 Version:           19.03.12
 API version:       1.40
 Go version:        go1.13.10
 Git commit:        48a66213fe
 Built:             Mon Jun 22 15:46:54 2020
 OS/Arch:           linux/amd64
 Experimental:      false

Server: Docker Engine - Community
 Engine:
  Version:          19.03.12
  API version:      1.40 (minimum version 1.12)
  Go version:       go1.13.10
  Git commit:       48a66213fe
  Built:            Mon Jun 22 15:45:28 2020
  OS/Arch:          linux/amd64
  Experimental:     false
 containerd:
  Version:          1.2.13
  GitCommit:        7ad184331fa3e55e52b890ea95e65ba581ae3429
 runc:
  Version:          1.0.0-rc10
  GitCommit:        dc9208a3303feef5b3839f4323d9beb36df0a9dd
 docker-init:
  Version:          0.18.0
  GitCommit:        fec3683

[root@cdss-server1 ~]# runc --version
runc version 1.0.0-rc10
commit: dc9208a3303feef5b3839f4323d9beb36df0a9dd
spec: 1.0.1-dev