raspberry pi common : kubeadm で csgroups の memory を有効にする必要がある

[sugardon]

エラー

$ sudo kubeadm init --v=5
I0103 15:23:21.651337   32040 initconfiguration.go:103] detected and using CRI socket: /var/run/dockershim.sock
I0103 15:23:21.651872   32040 interface.go:400] Looking for default routes with IPv4 addresses
I0103 15:23:21.651904   32040 interface.go:405] Default route transits interface "eth0"
I0103 15:23:21.653072   32040 interface.go:208] Interface eth0 is up
I0103 15:23:21.653582   32040 interface.go:256] Interface "eth0" has 2 addresses :[192.168.21.12/24 fe80::dea6:32ff:fedb:83d6/64].
I0103 15:23:21.653694   32040 interface.go:223] Checking addr  192.168.21.12/24.
I0103 15:23:21.653730   32040 interface.go:230] IP found 192.168.21.12
I0103 15:23:21.653766   32040 interface.go:262] Found valid IPv4 address 192.168.21.12 for interface "eth0".
I0103 15:23:21.653816   32040 interface.go:411] Found active IP 192.168.21.12 
I0103 15:23:21.654224   32040 version.go:183] fetching Kubernetes version from URL: https://dl.k8s.io/release/stable-1.txt
I0103 15:23:22.185790   32040 version.go:252] remote version is much newer: v1.20.1; falling back to: stable-1.18
I0103 15:23:22.185967   32040 version.go:183] fetching Kubernetes version from URL: https://dl.k8s.io/release/stable-1.18.txt
W0103 15:23:22.539079   32040 configset.go:202] WARNING: kubeadm cannot validate component configs for API groups [kubelet.config.k8s.io kubeproxy.config.k8s.io]
[init] Using Kubernetes version: v1.18.14
[preflight] Running pre-flight checks
I0103 15:23:22.541107   32040 checks.go:577] validating Kubernetes and kubeadm version
I0103 15:23:22.541241   32040 checks.go:166] validating if the firewall is enabled and active
I0103 15:23:22.577641   32040 checks.go:201] validating availability of port 6443
I0103 15:23:22.578368   32040 checks.go:201] validating availability of port 10259
I0103 15:23:22.578553   32040 checks.go:201] validating availability of port 10257
I0103 15:23:22.578732   32040 checks.go:286] validating the existence of file /etc/kubernetes/manifests/kube-apiserver.yaml
I0103 15:23:22.578887   32040 checks.go:286] validating the existence of file /etc/kubernetes/manifests/kube-controller-manager.yaml
I0103 15:23:22.579006   32040 checks.go:286] validating the existence of file /etc/kubernetes/manifests/kube-scheduler.yaml
I0103 15:23:22.579092   32040 checks.go:286] validating the existence of file /etc/kubernetes/manifests/etcd.yaml
I0103 15:23:22.579149   32040 checks.go:432] validating if the connectivity type is via proxy or direct
I0103 15:23:22.579234   32040 checks.go:471] validating http connectivity to first IP address in the CIDR
I0103 15:23:22.579311   32040 checks.go:471] validating http connectivity to first IP address in the CIDR
I0103 15:23:22.579348   32040 checks.go:102] validating the container runtime
I0103 15:23:22.833881   32040 checks.go:128] validating if the service is enabled and active
I0103 15:23:23.158665   32040 checks.go:335] validating the contents of file /proc/sys/net/bridge/bridge-nf-call-iptables
I0103 15:23:23.158873   32040 checks.go:335] validating the contents of file /proc/sys/net/ipv4/ip_forward
I0103 15:23:23.159004   32040 checks.go:649] validating whether swap is enabled or not
I0103 15:23:23.159127   32040 checks.go:376] validating the presence of executable conntrack
I0103 15:23:23.159218   32040 checks.go:376] validating the presence of executable ip
I0103 15:23:23.159293   32040 checks.go:376] validating the presence of executable iptables
I0103 15:23:23.159371   32040 checks.go:376] validating the presence of executable mount
I0103 15:23:23.159444   32040 checks.go:376] validating the presence of executable nsenter
I0103 15:23:23.159540   32040 checks.go:376] validating the presence of executable ebtables
I0103 15:23:23.159624   32040 checks.go:376] validating the presence of executable ethtool
I0103 15:23:23.159692   32040 checks.go:376] validating the presence of executable socat
I0103 15:23:23.159765   32040 checks.go:376] validating the presence of executable tc
I0103 15:23:23.159818   32040 checks.go:376] validating the presence of executable touch
I0103 15:23:23.159879   32040 checks.go:520] running all checks
[preflight] The system verification failed. Printing the output from the verification:
KERNEL_VERSION: 5.4.0-1025-raspi
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_INET: enabled
CONFIG_EXT4_FS: enabled
CONFIG_PROC_FS: enabled
CONFIG_NETFILTER_XT_TARGET_REDIRECT: enabled (as module)
CONFIG_NETFILTER_XT_MATCH_COMMENT: enabled (as module)
CONFIG_OVERLAY_FS: enabled (as module)
CONFIG_AUFS_FS: enabled (as module)
CONFIG_BLK_DEV_DM: enabled
DOCKER_VERSION: 19.03.14
DOCKER_GRAPH_DRIVER: overlay2
OS: Linux
CGROUPS_CPU: enabled
CGROUPS_CPUACCT: enabled
CGROUPS_CPUSET: enabled
CGROUPS_DEVICES: enabled
CGROUPS_FREEZER: enabled
CGROUPS_MEMORY: missing
I0103 15:23:23.606685   32040 checks.go:406] checking whether the given node name is reachable using net.LookupHost
I0103 15:23:23.606742   32040 checks.go:618] validating kubelet version
I0103 15:23:23.771803   32040 checks.go:128] validating if the service is enabled and active
I0103 15:23:23.810045   32040 checks.go:201] validating availability of port 10250
I0103 15:23:23.810574   32040 checks.go:201] validating availability of port 2379
I0103 15:23:23.810914   32040 checks.go:201] validating availability of port 2380
I0103 15:23:23.811191   32040 checks.go:249] validating the existence and emptiness of directory /var/lib/etcd
[preflight] Some fatal errors occurred:
        [ERROR FileAvailable--etc-kubernetes-manifests-kube-apiserver.yaml]: /etc/kubernetes/manifests/kube-apiserver.yaml already exists
        [ERROR FileAvailable--etc-kubernetes-manifests-kube-controller-manager.yaml]: /etc/kubernetes/manifests/kube-controller-manager.yaml already exists
        [ERROR FileAvailable--etc-kubernetes-manifests-kube-scheduler.yaml]: /etc/kubernetes/manifests/kube-scheduler.yaml already exists
        [ERROR SystemVerification]: missing cgroups: memory

暫定回避

$ cat /proc/cgroups
#subsys_name    hierarchy       num_cgroups     enabled
cpuset  6       5       1
cpu     9       103     1
cpuacct 9       103     1
blkio   3       103     1
memory  0       112     0
devices 7       103     1
freezer 5       6       1
net_cls 2       5       1
perf_event      10      5       1
net_prio        2       5       1
pids    8       111     1
rdma    4       1       1

0 で無効だったので、手で追加

$ sudo vim /boot/firmware/cmdline.txt
$ cat /boot/firmware/cmdline.txt 
net.ifnames=0 dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=LABEL=writable rootfstype=ext4 elevator=deadline rootwait fixrtc cgroup_enable=memory

再起動

$ cat /proc/cgroups
#subsys_name    hierarchy       num_cgroups     enabled
cpuset  4       17      1
cpu     7       60      1
cpuacct 7       60      1
blkio   6       60      1
memory  8       106     1
devices 10      60      1
freezer 5       18      1
net_cls 11      17      1
perf_event      3       17      1
net_prio        11      17      1
pids    2       65      1
rdma    9       1       1

有効になっていそうだった