kubelet log path 변경

현재 k8s 자동 프로비저닝 툴을 개발 중입니다.

kubelet log가 쌓이는 경로를 바꾸고 싶어요!

선택사항

v1.31.1 기준

• 필수 binary 파일인 kube-log-runner를 다운로드 받는다.
  • kubernetes 패키지 목록

👀 자 드가자

1, 2번은 systemd 파일을 직접 변경해하는 방식으로 진행한다.
3번은 kubelet을 직접 실행하는 방식으로 진행한다.

1번

• kubernetes system logs를 보면 kube-log-runner를 사용하는 방법
  • kube-log-runner 사용법
• 아래의 ExecStart를 변경하여 작성한다.

root@temp-cp-node-1:/usr/lib/systemd/system/kubelet.service.d# cat 10-kubeadm.conf
# Note: This dropin only works with kubeadm and kubelet v1.11+
[Service]
Environment="KUBELET_KUBECONFIG_ARGS=--bootstrap-kubeconfig=/etc/kubernetes/bootstrap-kubelet.conf --kubeconfig=/etc/kubernetes/kubelet.conf"
Environment="KUBELET_CONFIG_ARGS=--config=/var/lib/kubelet/config.yaml"
# This is a file that "kubeadm init" and "kubeadm join" generates at runtime, populating the KUBELET_KUBEADM_ARGS variable dynamically
EnvironmentFile=-/var/lib/kubelet/kubeadm-flags.env
# This is a file that the user can use for overrides of the kubelet args as a last resort. Preferably, the user should use
# the .NodeRegistration.KubeletExtraArgs object in the configuration files instead. KUBELET_EXTRA_ARGS should be sourced from this file.
EnvironmentFile=-/etc/default/kubelet
ExecStart=
ExecStart=/usr/bin/kube-log-runner -log-file=/data/log/kubelet.log -also-stdout=false \
  /usr/bin/kubelet $KUBELET_KUBECONFIG_ARGS $KUBELET_CONFIG_ARGS $KUBELET_KUBEADM_ARGS $KUBELET_EXTRA_ARGS

---

2번

• systemd 자체 유닛 기능을 이용하여 변경하는 방법
  • systemd docs

root@temp-cp-node-1:~# cat /usr/lib/systemd/system/kubelet.service.d/10-kubeadm.conf
# Note: This dropin only works with kubeadm and kubelet v1.11+
[Service]
Environment="KUBELET_KUBECONFIG_ARGS=--bootstrap-kubeconfig=/etc/kubernetes/bootstrap-kubelet.conf --kubeconfig=/etc/kubernetes/kubelet.conf"
Environment="KUBELET_CONFIG_ARGS=--config=/var/lib/kubelet/config.yaml"
# This is a file that "kubeadm init" and "kubeadm join" generates at runtime, populating the KUBELET_KUBEADM_ARGS variable dynamically
EnvironmentFile=-/var/lib/kubelet/kubeadm-flags.env
# This is a file that the user can use for overrides of the kubelet args as a last resort. Preferably, the user should use
# the .NodeRegistration.KubeletExtraArgs object in the configuration files instead. KUBELET_EXTRA_ARGS should be sourced from this file.
EnvironmentFile=-/etc/default/kubelet
ExecStart=
ExecStart=/usr/bin/kubelet $KUBELET_KUBECONFIG_ARGS $KUBELET_CONFIG_ARGS $KUBELET_KUBEADM_ARGS $KUBELET_EXTRA_ARGS
StandardOutput=append:/data/log/kubelet.log
StandardError=append:/data/log/kubelet.log

StandardOutput, StandardError를 추가하면 아래 정의한 경로로 지속하여 추가된다.

StandardOutput=append:/data/log/kubelet.log
StandardError=append:/data/log/kubelet.log

---

3번

• systemd를 이용하는 방식이 아닌 kubelet 명령어를 직접 실행하는 방식
  • 해당 방식을 백그라운드로 실행하야할듯하다.(마지막에 &를 붙혀준다.)

test@temp-cp-node-1:~$ sudo ./kube-log-runner -log-file=/data/log/kubelet.log -also-stdout=false /usr/bin/kubelet --bootstrap-kubeconfig=/etc/kubernetes/bootstrap-kubelet.conf --kubeconfig=/etc/kubernetes/kubelet.conf --config=/var/lib/kubelet/config.yaml --container-runtime-endpoint=unix:///run/containerd/containerd.sock --pod-infra-container-image=registry.k8s.io/pause:3.10 --root-dir=/data/kubelet --v=2 --runtime-request-timeout=15m --resolv-conf=/run/systemd/resolve/resolv.conf --node-ip=10.10.40.82 --node-labels=[세부 설정]/role=master,[세부 설정]/clusterid=kubernetes,[세부 설정]/ansible_host=192.168.88.24
2024/10/25 01:14:02 Running command:
Command env: (log-file=/data/log/kubelet.log, also-stdout=false, redirect-stderr=true)
Run from directory:
Executable path: /usr/bin/kubelet
Args (comma-delimited): /usr/bin/kubelet,--bootstrap-kubeconfig=/etc/kubernetes/bootstrap-kubelet.conf,--kubeconfig=/etc/kubernetes/kubelet.conf,--config=/var/lib/kubelet/config.yaml,--container-runtime-endpoint=unix:///run/containerd/containerd.sock,--pod-infra-container-image=registry.k8s.io/pause:3.10,--root-dir=/data/kubelet,--v=2,--runtime-request-timeout=15m,--resolv-conf=/run/systemd/resolve/resolv.conf,--node-ip=10.10.40.82,--node-labels=[세부 설정]/role=master,[세부 설정]/clusterid=kubernetes,[세부 설정]/ansible_host=192.168.88.24
2024/10/25 01:14:02 Now listening for interrupts

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