kubeadminit用不正确的IP地址启动集群

Question

我初始化一个5节点的k8s集群，如下所示：

[root@lpdkubpoc01a ~]# kubeadm init --pod-network-cidr=10.96.0.0/16 --service-cidr=10.97.0.0/16 --image-repository quaytest.phx.aexp.com/control-plane
W0727 15:19:51.123991    1866 version.go:101] could not fetch a Kubernetes version from the internet: unable to get URL "https://dl.k8s.io/release/stable-1.txt": Get https://dl.k8s.io/release/stable-1.txt: dial tcp: lookup dl.k8s.io on 10.2.88.196:53: no such host
W0727 15:19:51.124080    1866 version.go:102] falling back to the local client version: v1.17.5
W0727 15:19:51.124236    1866 validation.go:28] Cannot validate kube-proxy config - no validator is available
W0727 15:19:51.124244    1866 validation.go:28] Cannot validate kubelet config - no validator is available
[init] Using Kubernetes version: v1.17.5
[preflight] Running pre-flight checks
...
...
Your Kubernetes control-plane has initialized successfully!
To start using your cluster, you need to run the following as a regular user:
```bash
mkdir -p $HOME/.kube
sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

您现在应该向集群部署一个pod网络。运行"；kubectl apply-f[podnetwork]；其中一个选项列在：https://kubernetes.io/docs/concepts/cluster-administration/addons/

然后，您可以通过以root身份在每个工作节点上运行以下操作来加入任意数量的工作节点：

kubeadm join 10.22.76.244:6443 --token fa5ia8.oqs7jv9ii6wzex0w 
--discovery-token-ca-cert-hash sha256:6680c99e6c49e0dce4522bc9768bfc2e7e2b38f5a10668d3a544554ab0d09ff1

我按照上面的说明运行以下程序：

[root@lpdkubpoc01a ~]# mkdir -p $HOME/.kube
[root@lpdkubpoc01a ~]# cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
cp: overwrite ‘/root/.kube/config’? y
[root@lpdkubpoc01a ~]# chown $(id -u):$(id -g) $HOME/.kube/config

但当我检查控制平面组件吊舱时，我看到它们都用初始化了

1. 相同的IP地址

2. 不正确的CIDR＝>似乎在主机网络中，这是一个很大的NO-NO

   [root@lpdkubpoc01a ~]# kubectl get pods -n kube-system -owide
   NAME                                                READY   STATUS    
   RESTARTS   AGE   IP             NODE                        NOMINATED NODE   READINESS GATES
   coredns-598947db54-dzrjk                            0/1     Pending   0          37s   <none>         <none>                      <none>           <none>
   coredns-598947db54-t2wch                            0/1     Pending   0          37s   <none>         <none>                      <none>           <none>
   etcd-lpdkubpoc01a.phx.aexp.com                      1/1     Running   0          50s   10.22.76.244   lpdkubpoc01a.phx.aexp.com   <none>           <none>
   kube-apiserver-lpdkubpoc01a.phx.aexp.com            1/1     Running   0          50s   10.22.76.244   lpdkubpoc01a.phx.aexp.com   <none>           <none>
   kube-controller-manager-lpdkubpoc01a.phx.aexp.com   1/1     Running   0          50s   10.22.76.244   lpdkubpoc01a.phx.aexp.com   <none>           <none>
   kube-proxy-8dbx2                                    1/1     Running   0          38s   10.22.76.244   lpdkubpoc01a.phx.aexp.com   <none>           <none>
   kube-scheduler-lpdkubpoc01a.phx.aexp.com            1/1     Running   0          50s   10.22.76.244   lpdkubpoc01a.phx.aexp.com   <none>           <none>
   

出了什么问题，我该如何补救？kube系统ns中的pod不应该与主机具有相同的IP，也绝对不在同一网络中：

[root@lpdkubpoc01a ~]# ifconfig
docker0: flags=4099<UP,BROADCAST,MULTICAST>  mtu 1500
inet 172.17.0.1  netmask 255.255.0.0  broadcast 0.0.0.0
ether 02:42:40:17:25:e4  txqueuelen 0  (Ethernet)
RX packets 0  bytes 0 (0.0 B)
RX errors 0  dropped 0  overruns 0  frame 0
TX packets 0  bytes 0 (0.0 B)
TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
**eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
inet 10.22.76.244  netmask 255.255.254.0  broadcast 10.22.77.255
ether 00:50:56:b8:e1:84  txqueuelen 1000  (Ethernet)
RX packets 73810789  bytes 8755922965 (8.1 GiB)
RX errors 0  dropped 31388  overruns 0  frame 0
TX packets 44487774  bytes 12389932340 (11.5 GiB)
TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0**
eth1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 9000
inet 10.0.195.100  netmask 255.255.254.0  broadcast 10.0.195.255
ether 00:50:56:b8:6c:23  txqueuelen 1000  (Ethernet)
RX packets 3573616  bytes 708218742 (675.4 MiB)
RX errors 0  dropped 50118  overruns 0  frame 0
TX packets 830522  bytes 174979700 (166.8 MiB)
TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
inet 127.0.0.1  netmask 255.0.0.0
loop  txqueuelen 1000  (Local Loopback)
RX packets 263222455  bytes 44942504690 (41.8 GiB)
RX errors 0  dropped 0  overruns 0  frame 0
TX packets 263222455  bytes 44942504690 (41.8 GiB)
TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

谢谢！

Answer 1

看起来你的pod网络还没有配置好。你可以安装Calico或Weave之类的东西。你的coredns pod应该在那之后出现，你的其他pod也应该得到不同的IP地址。

过去，这些说明在kubeadm主页上，但据我所知，它们实际上已经被弃用，转而支持在CNI上进行更多标准化，并让每个CNI提供商提供自己的安装说明。

✌️

Answer 2

控制平面组件是statics pod，您可以在/etc/kubernetes/manifest/目录中看到它们的yaml文件，主节点的kubelete负责检查它们是否正在运行。因此，静态pod拥有本地主机的IP是正常的。

顺便说一句，你仍然需要一个kubernetes网络插件，如Calico或Weave net。请检查此链接
https://kubernetes.io/docs/concepts/cluster-administration/addons/
例如，在您的情况下，您只需要运行此命令即可使用您想要的pod网络cidr:

部署编织网络插件

kubectl应用-f"；https://cloud.weave.works/k8s/net?k8s-version=$(kubectl version | base64 | tr-d'\n'(&env。IPALLOC_ RANGE＝10.96.0/16"；

在部署网络插件时，请小心指定您的pod网络cidr。

Answer 3

控制平面pod具有节点ip是正常的。其他一切都将从cni获得ip。