.. _kind_run_simple_container: ====================== 在kind运行简单的容器 ====================== 采用 :ref:`alpine_docker_image` 来从0开始一步步完成完整的应用服务器运行集群: 将我的 :ref:`cloud_atlas` WEB网站( :ref:`sphinx_doc` )部署到 :ref:`kubernetes` 模拟 :ref:`kind` 集群中，作为 :ref:`workload_resources` 运行... 准备工作 ================ - 首先结合 :ref:`kind_local_registry` 部署一个 :ref:`kind_multi_node` (快速脚本可以采用 :ref:`kind_local_registry` 整合好的脚本 ``kind-with-registry-arm.sh`` ): .. literalinclude:: kind_run_simple_container/create_kind_multi_node_local_registry :language: bash :caption: 执行kind-with-registry-arm.sh创建具备本地Registry的kind多节点集群 - 采用 :ref:`alpine_docker_image` 创建的 :ref:`alipine-nginx` 镜像: .. literalinclude:: kind_run_simple_container/build_alpine-nginx_image_push_local_registry :language: bash :caption: 创建具备nginx的alpine linux镜像并推送到本地Registry 运行容器 =========== - 准备一个简单 :ref:`workload_resources` : 运行2个pod ``deployment-simple.yaml`` : .. literalinclude:: kind_run_simple_container/deployment-simple.yaml :language: yaml :caption: 简单运行2个pod的deployment-simple.yaml - 部署采用 ``kubectl create`` : .. literalinclude:: kind_run_simple_container/kubectl_create_deployment-simple :language: bash :caption: kubectl执行部署 pod创建问题排查 ----------------- - 检查:: kubectl get pods -o wide 可以看到:: NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES nginx-deployment-c64787574-j5hsl 0/1 CrashLoopBackOff 4 (31s ago) 2m4s 10.244.3.3 dev-worker2 nginx-deployment-c64787574-n6wvw 0/1 CrashLoopBackOff 4 (27s ago) 2m4s 10.244.5.2 dev-worker4 启动失败 ``CrashLoopBackOff`` ，参考 :ref:`k8s_crashloopbackoff` - 检查pod详情采用 ``kubectl describe pods`` 命令:: kubectl describe pods nginx-deployment-c64787574-j5hsl 可以看到事件如下:: Events: Type Reason Age From Message ---- ------ ---- ---- ------- Normal Scheduled 3m45s default-scheduler Successfully assigned default/nginx-deployment-c64787574-j5hsl to dev-worker2 Normal Pulling 3m45s kubelet Pulling image "localhost:5001/alpine-nginx:20221126-01" Normal Pulled 3m45s kubelet Successfully pulled image "localhost:5001/alpine-nginx:20221126-01" in 138.657406ms Normal Created 2m13s (x5 over 3m45s) kubelet Created container nginx Normal Started 2m13s (x5 over 3m45s) kubelet Started container nginx Normal Pulled 2m13s (x4 over 3m44s) kubelet Container image "localhost:5001/alpine-nginx:20221126-01" already present on machine Warning BackOff 2m12s (x9 over 3m43s) kubelet Back-off restarting failed container 为何启动容器失败? 需要注意到Kubernetes需要能够正确诊断容器启动状态 :ref:`k8s_health_check` ，这里检测 ``liveness`` 就是通过端口服务完成检测。 但是，很不巧 :ref:`alipine-nginx` 所使用的 :ref:`alpine_linux` 发行版提供的 :ref:`nginx` 软件包，默认采用了一个禁止访问的 ``default.conf`` 配置。这个 ``404`` 返回页面会使得 :ref:`k8s_health_check` 失败。 检查 ======= 当 :ref:`alipine-nginx` 配置正确，能够在 :ref:`kind` 集群中运行简单的nginx服务之后，此时检查:: kubectl get pods 就能看到:: NAME READY STATUS RESTARTS AGE alpine-nginx-deployment-7cb557b55b-6jdj8 1/1 Running 0 32m alpine-nginx-deployment-7cb557b55b-9zt6q 1/1 Running 0 32m 下一步 ======= 下面我们来构建: - 使用 :ref:`btrfs_nfs` 提供共享存储 - 配置 :ref:`k8s_nfs` 将共享卷中我的 ``cloud-atlas`` build好的html作为NGINX的目录(配置和上文Docker运行方式类似)