基于containerd容器运行时部署k8s 1.28集群
一、主机准备
1.1 主机操作系统说明
序号操作系统及版本备注1CentOS7u9
1.2 主机硬件配置说明
需求CPU内存硬盘角色主机名值8C8G1024GBmasterk8s-master01值8C16G1024GBworker(node)k8s-worker01值8C16G1024GBworker(node)k8s-worker02
1.3 主机配置
1.3.1 主机名配置
由于本次使用3台主机完成kubernetes集群部署，其中1台为master节点,名称为k8s-master01;其中2台为worker节点，名称分别为：k8s-worker01及k8s-worker02
master节点
# hostnamectl set-hostname k8s-master01
worker01节点
# hostnamectl set-hostname k8s-worker01
worker02节点
# hostnamectl set-hostname k8s-worker02
1.3.2 主机IP地址配置
k8s-master节点IP地址为：192.168.10.140/24
# vim /etc/sysconfig/network-scripts/ifcfg-ens33
TYPE="Ethernet"
PROXY_METHOD="none"
BROWSER_ONLY="no"
BOOTPROTO="none"
DEFROUTE="yes"
IPV4_FAILURE_FATAL="no"
IPV6INIT="yes"
IPV6_AUTOCONF="yes"
IPV6_DEFROUTE="yes"
IPV6_FAILURE_FATAL="no"
IPV6_ADDR_GEN_MODE="stable-privacy"
NAME="ens33"
DEVICE="ens33"
ONBOOT="yes"
IPADDR="192.168.10.140"
PREFIX="24"
GATEWAY="192.168.10.2"
DNS1="119.29.29.29"
k8s-worker1节点IP地址为：192.168.10.141/24
# vim /etc/sysconfig/network-scripts/ifcfg-ens33
TYPE="Ethernet"
PROXY_METHOD="none"
BROWSER_ONLY="no"
BOOTPROTO="none"
DEFROUTE="yes"
IPV4_FAILURE_FATAL="no"
IPV6INIT="yes"
IPV6_AUTOCONF="yes"
IPV6_DEFROUTE="yes"
IPV6_FAILURE_FATAL="no"
IPV6_ADDR_GEN_MODE="stable-privacy"
NAME="ens33"
DEVICE="ens33"
ONBOOT="yes"
IPADDR="192.168.10.141"
PREFIX="24"
GATEWAY="192.168.10.2"
DNS1="119.29.29.29"
k8s-worker2节点IP地址为：192.168.10.142/24
# vim /etc/sysconfig/network-scripts/ifcfg-ens33
TYPE="Ethernet"
PROXY_METHOD="none"
BROWSER_ONLY="no"
BOOTPROTO="none"
DEFROUTE="yes"
IPV4_FAILURE_FATAL="no"
IPV6INIT="yes"
IPV6_AUTOCONF="yes"
IPV6_DEFROUTE="yes"
IPV6_FAILURE_FATAL="no"
IPV6_ADDR_GEN_MODE="stable-privacy"
NAME="ens33"
DEVICE="ens33"
ONBOOT="yes"
IPADDR="192.168.10.142"
PREFIX="24"
GATEWAY="192.168.10.2"
DNS1="119.29.29.29"
1.3.3 主机名与IP地址解析
所有集群主机均需要进行配置。
# cat /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.10.140 k8s-master01
192.168.10.141 k8s-worker01
192.168.10.142 k8s-worker02
1.3.4 防火墙配置
所有主机均需要操作。
关闭现有防火墙firewalld
# systemctl disable firewalld
# systemctl stop firewalld
# firewall-cmd --state
not running
1.3.5 SELINUX配置
所有主机均需要操作。修改SELinux配置需要重启操作系统。
# sed -ri 's/SELINUX=enforcing/SELINUX=disabled/' /etc/selinux/config
# sestatus
1.3.6 时间同步配置
所有主机均需要操作。最小化安装系统需要安装ntpdate软件。
# crontab -l
0 */1 * * * /usr/sbin/ntpdate time1.aliyun.com
1.3.7 升级操作系统内核
所有主机均需要操作。
导入elrepo gpg key
# rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
安装elrepo YUM源仓库
# yum -y install https://www.elrepo.org/elrepo-release-7.0-4.el7.elrepo.noarch.rpm
安装kernel-ml版本，ml为最新稳定版本，lt为长期维护版本
# yum --enablerepo="elrepo-kernel" -y install kernel-lt.x86_64
设置grub2默认引导为0
# grub2-set-default 0
重新生成grub2引导文件
# grub2-mkconfig -o /boot/grub2/grub.cfg
更新后，需要重启，使用升级的内核生效。
# reboot
重启后，需要验证内核是否为更新对应的版本
# uname -r
1.3.8 配置内核转发及网桥过滤
所有主机均需要操作。
添加网桥过滤及内核转发配置文件
# cat > /etc/sysctl.d/k8s.conf << EOF
net.bridge.bridge-nf-call-ip6tables = 1
net.bridge.bridge-nf-call-iptables = 1
net.ipv4.ip_forward = 1
vm.swappiness = 0
EOF
加载br_netfilter模块
# modprobe br_netfilter
查看是否加载
# lsmod | grep br_netfilter
br_netfilter 22256 0
bridge 151336 1 br_netfilter
1.3.9 安装ipset及ipvsadm
所有主机均需要操作。
安装ipset及ipvsadm
# yum -y install ipset ipvsadm
配置ipvsadm模块加载方式
添加需要加载的模块
# cat > /etc/sysconfig/modules/ipvs.modules < #!/bin/bash modprobe -- ip_vs modprobe -- ip_vs_rr modprobe -- ip_vs_wrr modprobe -- ip_vs_sh modprobe -- nf_conntrack EOF 授权、运行、检查是否加载 # chmod 755 /etc/sysconfig/modules/ipvs.modules && bash /etc/sysconfig/modules/ipvs.modules && lsmod | grep -e ip_vs -e nf_conntrack 1.3.10 关闭SWAP分区 修改完成后需要重启操作系统，如不重启，可临时关闭，命令为swapoff -a 永远关闭swap分区，需要重启操作系统 # cat /etc/fstab ...... # /dev/mapper/centos-swap swap swap defaults 0 0 在上一行中行首添加# 二、容器运行时 Containerd准备 2.1 Containerd准备 2.1.1 Containerd部署文件获取 # wget https://github.com/containerd/containerd/releases/download/v1.7.3/cri-containerd-1.7.3-linux-amd64.tar.gz # tar xf cri-containerd-1.7.3-linux-amd64.tar.gz -C / 2.1.2 Containerd配置文件生成并修改 # mkdir /etc/containerd # containerd config default > /etc/containerd/config.toml # vim /etc/containerd/config.toml sandbox_image = "registry.k8s.io/pause:3.9" 由3.8修改为3.9 2.1.3 Containerd启动及开机自启动 # systemctl enable --now containerd 验证其版本 # containerd --version 2.2 runc准备 2.2.1 libseccomp准备 # wget https://github.com/opencontainers/runc/releases/download/v1.1.5/libseccomp-2.5.4.tar.gz # tar xf libseccomp-2.5.4.tar.gz # cd libseccomp-2.5.4/ # yum install gperf -y # ./configure # make && make install # find / -name "libseccomp.so" 2.2.2 runc安装 # wget https://github.com/opencontainers/runc/releases/download/v1.1.9/runc.amd64 # chmod +x runc.amd64 查找containerd安装时已安装的runc所在的位置，然后替换 # which runc 替换containerd安装已安装的runc # mv runc.amd64 /usr/local/sbin/runc 执行runc命令，如果有命令帮助则为正常 # runc 如果运行runc命令时提示：runc: error while loading shared libraries: libseccomp.so.2: cannot open shared object file: No such file or directory，则表明runc没有找到libseccomp，需要检查libseccomp是否安装，本次安装默认就可以查询到。 三、K8S集群部署 3.1 K8S集群软件YUM源准备 3.1.1 google提供YUM源 # cat > /etc/yum.repos.d/k8s.repo < [kubernetes] name=Kubernetes baseurl=https://packages.cloud.google.com/yum/repos/kubernetes-el7-x86_64 enabled=1 gpgcheck=1 repo_gpgcheck=1 gpgkey=https://packages.cloud.google.com/yum/doc/yum-key.gpg https://packages.cloud.google.com/yum/doc/rpm-package-key.gpg EOF 3.1.2 阿里云提供YUM源 # cat > /etc/yum.repos.d/k8s.repo < [kubernetes] name=Kubernetes baseurl=https://mirrors.aliyun.com/kubernetes/yum/repos/kubernetes-el7-x86_64/ enabled=1 gpgcheck=0 repo_gpgcheck=0 gpgkey=https://mirrors.aliyun.com/kubernetes/yum/doc/yum-key.gpg https://mirrors.aliyun.com/kubernetes/yum/doc/rpm-package-key.gpg EOF 3.2 K8S集群软件安装 3.2.1 集群软件安装 所有节点均可安装 默认安装 # yum -y install kubeadm kubelet kubectl 查看指定版本 # yum list kubeadm.x86_64 --showduplicates | sort -r # yum list kubelet.x86_64 --showduplicates | sort -r # yum list kubectl.x86_64 --showduplicates | sort -r 安装指定版本 # yum -y install kubeadm-1.28.X-0 kubelet-1.28.X-0 kubectl-1.28.X-0 3.2.2 配置kubelet 为了实现docker使用的cgroupdriver与kubelet使用的cgroup的一致性，建议修改如下文件内容。 # vim /etc/sysconfig/kubelet KUBELET_EXTRA_ARGS="--cgroup-driver=systemd" 设置kubelet为开机自启动即可，由于没有生成配置文件，集群初始化后自动启动 # systemctl enable kubelet 3.3 K8S集群初始化 3.3.1 替换100年证书kubeadm # which kubeadm /usr/bin/kubeadm 3.3.1.1 获取kubernetes源码 [root@k8s-master01 ~]# wget https://github.com/kubernetes/kubernetes/archive/refs/tags/v1.28.0.tar.gz [root@k8s-master01 ~]# ls v1.28.0.tar.gz [root@k8s-master01 ~]# tar xf v1.28.0.tar.gz [root@k8s-master01 ~]# ls kubernetes-1.28.0 3.3.1.2 修改kubernetes源码 修改CA证书为100年有效期（默认为10年） [root@k8s-master01 ~]# vim kubernetes-1.28.0/staging/src/k8s.io/client-go/util/cert/cert.go 72 tmpl := x509.Certificate{ 73 SerialNumber: serial, 74 Subject: pkix.Name{ 75 CommonName: cfg.CommonName, 76 Organization: cfg.Organization, 77 }, 78 DNSNames: []string{cfg.CommonName}, 79 NotBefore: notBefore, 80 NotAfter: now.Add(duration365d * 100).UTC(), 81 KeyUsage: x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature | x509.KeyUsageCertSign, 82 BasicConstraintsValid: true, 83 IsCA: true, 84 } 修改说明： 把文件中80行，10修改为100即可 。 修改kubeadm证书有效期为100年（默认为1年） [root@k8s-master01 ~]# vim kubernetes-1.28.0/cmd/kubeadm/app/constants/constants.go ...... 37 const ( 38 // KubernetesDir is the directory Kubernetes owns for storing various configuration files 39 KubernetesDir = "/etc/kubernetes" 40 // ManifestsSubDirName defines directory name to store manifests 41 ManifestsSubDirName = "manifests" 42 // TempDirForKubeadm defines temporary directory for kubeadm 43 // should be joined with KubernetesDir. 44 TempDirForKubeadm = "tmp" 45 46 // CertificateBackdate defines the offset applied to notBefore for CA certificates generated by kubeadm 47 CertificateBackdate = time.Minute * 5 48 // CertificateValidity defines the validity for all the signed certificates generated by kubeadm 49 CertificateValidity = time.Hour * 24 * 365 * 100 修改说明： 把CertificateValidity = time.Hour * 24 * 365 修改为：CertificateValidity = time.Hour * 24 * 365 * 100 3.3.1.3 安装Go [root@k8s-master01 ~]# wget https://go.dev/dl/go1.21.0.linux-amd64.tar.gz [root@k8s-master01 ~]# tar xf go1.21.0.linux-amd64.tar.gz [root@k8s-master01 ~]# mv go /usr/local/go [root@k8s-master01 ~]# vim /etc/profile [root@k8s-master01 ~]# cat /etc/profile ...... export PATH=$PATH:/usr/local/go/bin [root@k8s-master01 ~]# source /etc/profile [root@k8s-master01 ~]# go version go version go1.21.0 linux/amd64 3.3.1.4 kubernetes源码编译 [root@k8s-master01 ~]# cd kubernetes-1.28.0/ [root@k8s-master01 kubernetes-1.28.0]# make all WHAT=cmd/kubeadm GOFLAGS=-v [root@k8s-master01 kubernetes-1.28.0]# ls _output [root@k8s-master01 kubernetes-1.28.0]# ls _output/ bin local [root@k8s-master01 kubernetes-1.28.0]# ls _output/bin/ kubeadm ncpu 3.3.1.5 替换所有集群主机kubeadm [root@k8s-master01 kubernetes-1.28.0]# which kubeadm /usr/bin/kubeadm [root@k8s-master01 kubernetes-1.28.0]# rm -rf `which kubeadm` [root@k8s-master01 kubernetes-1.28.0]# cp _output/bin/kubeadm /usr/bin/kubeadm [root@k8s-master01 kubernetes-1.28.0]# which kubeadm /usr/bin/kubeadm [root@k8s-worker01 ~]# rm -rf `which kubeadm` [root@k8s-worker01 ~]# rm -rf `which kubeadm` [root@k8s-master01 kubernetes-1.28.0]# scp _output/bin/kubeadm 192.168.10.141:/usr/bin/kubeadm [root@k8s-master01 kubernetes-1.28.0]# scp _output/bin/kubeadm 192.168.10.142:/usr/bin/kubeadm 3.3.2 获取kubernetes 1.28组件容器镜像 [root@k8s-master01 ~]# kubeadm config images list registry.k8s.io/kube-apiserver:v1.28.0 registry.k8s.io/kube-controller-manager:v1.28.0 registry.k8s.io/kube-scheduler:v1.28.0 registry.k8s.io/kube-proxy:v1.28.0 registry.k8s.io/pause:3.9 registry.k8s.io/etcd:3.5.9-0 registry.k8s.io/coredns/coredns:v1.10.1 [root@k8s-master01 ~]# kubeadm config images pull 3.3.3 kubernetes 1.28集群初始化 [root@k8s-master01 ~]# kubeadm init --kubernetes-version=v1.28.0 --pod-network-cidr=10.244.0.0/16 --apiserver-advertise-address=192.168.10.140 --cri-socket unix:///var/run/containerd/containerd.sock [init] Using Kubernetes version: v1.28.0 [preflight] Running pre-flight checks [preflight] Pulling images required for setting up a Kubernetes cluster [preflight] This might take a minute or two, depending on the speed of your internet connection [preflight] You can also perform this action in beforehand using 'kubeadm config images pull' [certs] Using certificateDir folder "/etc/kubernetes/pki" [certs] Generating "ca" certificate and key [certs] Generating "apiserver" certificate and key [certs] apiserver serving cert is signed for DNS names [k8s-master01 kubernetes kubernetes.default kubernetes.default.svc kubernetes.default.svc.cluster.local] and IPs [10.96.0.1 192.168.10.140] [certs] Generating "apiserver-kubelet-client" certificate and key [certs] Generating "front-proxy-ca" certificate and key [certs] Generating "front-proxy-client" certificate and key [certs] Generating "etcd/ca" certificate and key [certs] Generating "etcd/server" certificate and key [certs] etcd/server serving cert is signed for DNS names [k8s-master01 localhost] and IPs [192.168.10.140 127.0.0.1 ::1] [certs] Generating "etcd/peer" certificate and key [certs] etcd/peer serving cert is signed for DNS names [k8s-master01 localhost] and IPs [192.168.10.140 127.0.0.1 ::1] [certs] Generating "etcd/healthcheck-client" certificate and key [certs] Generating "apiserver-etcd-client" certificate and key [certs] Generating "sa" key and public key [kubeconfig] Using kubeconfig folder "/etc/kubernetes" [kubeconfig] Writing "admin.conf" kubeconfig file [kubeconfig] Writing "kubelet.conf" kubeconfig file [kubeconfig] Writing "controller-manager.conf" kubeconfig file [kubeconfig] Writing "scheduler.conf" kubeconfig file [kubelet-start] Writing kubelet environment file with flags to file "/var/lib/kubelet/kubeadm-flags.env" [kubelet-start] Writing kubelet configuration to file "/var/lib/kubelet/config.yaml" [kubelet-start] Starting the kubelet [control-plane] Using manifest folder "/etc/kubernetes/manifests" [control-plane] Creating static Pod manifest for "kube-apiserver" [control-plane] Creating static Pod manifest for "kube-controller-manager" [control-plane] Creating static Pod manifest for "kube-scheduler" [etcd] Creating static Pod manifest for local etcd in "/etc/kubernetes/manifests" [wait-control-plane] Waiting for the kubelet to boot up the control plane as static Pods from directory "/etc/kubernetes/manifests". This can take up to 4m0s [apiclient] All control plane components are healthy after 20.502191 seconds [upload-config] Storing the configuration used in ConfigMap "kubeadm-config" in the "kube-system" Namespace [kubelet] Creating a ConfigMap "kubelet-config" in namespace kube-system with the configuration for the kubelets in the cluster [upload-certs] Skipping phase. Please see --upload-certs [mark-control-plane] Marking the node k8s-master01 as control-plane by adding the labels: [node-role.kubernetes.io/control-plane node.kubernetes.io/exclude-from-external-load-balancers] [mark-control-plane] Marking the node k8s-master01 as control-plane by adding the taints [node-role.kubernetes.io/control-plane:NoSchedule] [bootstrap-token] Using token: hd74hg.r8l1pe4tivwyjz73 [bootstrap-token] Configuring bootstrap tokens, cluster-info ConfigMap, RBAC Roles [bootstrap-token] Configured RBAC rules to allow Node Bootstrap tokens to get nodes [bootstrap-token] Configured RBAC rules to allow Node Bootstrap tokens to post CSRs in order for nodes to get long term certificate credentials [bootstrap-token] Configured RBAC rules to allow the csrapprover controller automatically approve CSRs from a Node Bootstrap Token [bootstrap-token] Configured RBAC rules to allow certificate rotation for all node client certificates in the cluster [bootstrap-token] Creating the "cluster-info" ConfigMap in the "kube-public" namespace [kubelet-finalize] Updating "/etc/kubernetes/kubelet.conf" to point to a rotatable kubelet client certificate and key [addons] Applied essential addon: CoreDNS [addons] Applied essential addon: kube-proxy Your Kubernetes control-plane has initialized successfully! To start using your cluster, you need to run the following as a regular user: mkdir -p $HOME/.kube sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config sudo chown $(id -u):$(id -g) $HOME/.kube/config Alternatively, if you are the root user, you can run: export KUBECONFIG=/etc/kubernetes/admin.conf You should now deploy a pod network to the cluster. Run "kubectl apply -f [podnetwork].yaml" with one of the options listed at: https://kubernetes.io/docs/concepts/cluster-administration/addons/ Then you can join any number of worker nodes by running the following on each as root: kubeadm join 192.168.10.140:6443 --token hd74hg.r8l1pe4tivwyjz73 \ --discovery-token-ca-cert-hash sha256:29a00daed8d96dfa8e913ab4c0a8c4037f1c253a20742ca8913932dd7c8b3bd1 3.4 工作节点加入集群 [root@k8s-worker01 ~]# kubeadm join 192.168.10.140:6443 --token hd74hg.r8l1pe4tivwyjz73 \ > --discovery-token-ca-cert-hash sha256:29a00daed8d96dfa8e913ab4c0a8c4037f1c253a20742ca8913932dd7c8b3bd1 --cri-socket unix:///var/run/containerd/containerd.sock [root@k8s-worker02 ~]# kubeadm join 192.168.10.140:6443 --token hd74hg.r8l1pe4tivwyjz73 \ > --discovery-token-ca-cert-hash sha256:29a00daed8d96dfa8e913ab4c0a8c4037f1c253a20742ca8913932dd7c8b3bd1 --cri-socket unix:///var/run/containerd/containerd.sock 3.5 验证K8S集群节点是否可用 [root@k8s-master01 ~]# kubectl get nodes NAME STATUS ROLES AGE VERSION k8s-master01 Ready control-plane 15m v1.28.0 k8s-worker01 Ready k8s-worker02 Ready 3.6 验证证书有效期 [root@k8s-master01 ~]# openssl x509 -in /etc/kubernetes/pki/apiserver.crt -noout -text | grep ' Not ' Not Before: Aug 21 10:24:00 2023 GMT Not After : Jul 28 10:29:00 2123 GMT [root@k8s-master01 ~]# kubeadm certs check-expiration [check-expiration] Reading configuration from the cluster... [check-expiration] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -o yaml' CERTIFICATE EXPIRES RESIDUAL TIME CERTIFICATE AUTHORITY EXTERNALLY MANAGED admin.conf Jul 28, 2123 10:29 UTC 99y ca no apiserver Jul 28, 2123 10:29 UTC 99y ca no apiserver-etcd-client Jul 28, 2123 10:29 UTC 99y etcd-ca no apiserver-kubelet-client Jul 28, 2123 10:29 UTC 99y ca no controller-manager.conf Jul 28, 2123 10:29 UTC 99y ca no etcd-healthcheck-client Jul 28, 2123 10:29 UTC 99y etcd-ca no etcd-peer Jul 28, 2123 10:29 UTC 99y etcd-ca no etcd-server Jul 28, 2123 10:29 UTC 99y etcd-ca no front-proxy-client Jul 28, 2123 10:29 UTC 99y front-proxy-ca no scheduler.conf Jul 28, 2123 10:29 UTC 99y ca no CERTIFICATE AUTHORITY EXPIRES RESIDUAL TIME EXTERNALLY MANAGED ca Aug 18, 2033 10:29 UTC 99y no etcd-ca Aug 18, 2033 10:29 UTC 99y no front-proxy-ca Aug 18, 2033 10:29 UTC 99y no 四、网络插件calico部署 calico访问链接：https://projectcalico.docs.tigera.io/about/about-calico # kubectl create -f https://raw.githubusercontent.com/projectcalico/calico/v3.26.1/manifests/tigera-operator.yaml # wget https://raw.githubusercontent.com/projectcalico/calico/v3.26.1/manifests/custom-resources.yaml # vim custom-resources.yaml # cat custom-resources.yaml # This section includes base Calico installation configuration. # For more information, see: https://projectcalico.docs.tigera.io/master/reference/installation/api#operator.tigera.io/v1.Installation apiVersion: operator.tigera.io/v1 kind: Installation metadata: name: default spec: # Configures Calico networking. calicoNetwork: # Note: The ipPools section cannot be modified post-install. ipPools: - blockSize: 26 cidr: 10.244.0.0/16 修改此行内容为初始化时定义的pod network cidr encapsulation: VXLANCrossSubnet natOutgoing: Enabled nodeSelector: all() --- # This section configures the Calico API server. # For more information, see: https://projectcalico.docs.tigera.io/master/reference/installation/api#operator.tigera.io/v1.APIServer apiVersion: operator.tigera.io/v1 kind: APIServer metadata: name: default spec: {} # kubectl create -f custom-resources.yaml installation.operator.tigera.io/default created apiserver.operator.tigera.io/default created [root@k8s-master01 ~]# kubectl get pods -n calico-system NAME READY STATUS RESTARTS AGE calico-kube-controllers-6bb86c78b4-cnr9l 1/1 Running 0 2m26s calico-node-86cs9 1/1 Running 0 2m26s calico-node-gjgcc 1/1 Running 0 2m26s calico-node-hlr69 1/1 Running 0 2m26s calico-typha-6f877c9d8f-8f5fb 1/1 Running 0 2m25s calico-typha-6f877c9d8f-spxqf 1/1 Running 0 2m26s csi-node-driver-9b8nd 2/2 Running 0 2m26s csi-node-driver-rg6dc 2/2 Running 0 2m26s csi-node-driver-tf82w 2/2 Running 0 2m26s operator.tigera.io/v1 kind: APIServer metadata: name: default spec: {} ~~~powershell # kubectl create -f custom-resources.yaml installation.operator.tigera.io/default created apiserver.operator.tigera.io/default created 推荐文章
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