尽管为它们设置了 clusterIP 服务，但我仍在努力处理 pod 之间的这种交叉通信。所有的 pod 都在同一个主节点上，并且在同一个命名空间中。总结:
$ kubectl get pods -o wide
NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES
nginx-744f4df6df-rxhph 1/1 Running 0 136m 10.42.0.31 raspberrypi <none> <none>
nginx-2-867f4f8859-csn48 1/1 Running 0 134m 10.42.0.32 raspberrypi <none> <none>
$ kubectl get svc -o wide
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
nginx-service ClusterIP 10.43.155.201 <none> 80/TCP 136m app=nginx
nginx-service2 ClusterIP 10.43.182.138 <none> 85/TCP 134m app=nginx-2
我无法从 nginx 容器内 curl http://nginx-service2:85，反之亦然...虽然我验证了这在我的 docker 桌面安装中有效:
# docker desktop
root@nginx-7dc45fbd74-7prml:/# curl http://nginx-service2:85
<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
# k3s
root@nginx-744f4df6df-rxhph:/# curl http://nginx-service2.pwk3spi-vraptor:85
curl: (6) Could not resolve host: nginx-service2.pwk3spi-vraptor
在谷歌搜索问题后(如果我错了请纠正我)这似乎是一个 coredns 问题，因为查看日志并查看错误超时:
$ kubectl get pods -n kube-system
NAME READY STATUS RESTARTS AGE
helm-install-traefik-qr2bd 0/1 Completed 0 153d
metrics-server-7566d596c8-nnzg2 1/1 Running 59 148d
svclb-traefik-kjbbr 2/2 Running 60 153d
traefik-758cd5fc85-wzjrn 1/1 Running 20 62d
local-path-provisioner-6d59f47c7-4hvf2 1/1 Running 72 148d
coredns-7944c66d8d-gkdp4 1/1 Running 0 3m47s
$ kubectl logs coredns-7944c66d8d-gkdp4 -n kube-system
.:53
[INFO] plugin/reload: Running configuration MD5 = 1c648f07b77ab1530deca4234afe0d03
CoreDNS-1.6.9
linux/arm, go1.14.1, 1766568
[ERROR] plugin/errors: 2 1898797220.1916943194. HINFO: read udp 10.42.0.38:50482->192.168.8.109:53: i/o timeout
[ERROR] plugin/errors: 2 1898797220.1916943194. HINFO: read udp 10.42.0.38:34160->192.168.8.109:53: i/o timeout
[ERROR] plugin/errors: 2 1898797220.1916943194. HINFO: read udp 10.42.0.38:53485->192.168.8.109:53: i/o timeout
[ERROR] plugin/errors: 2 1898797220.1916943194. HINFO: read udp 10.42.0.38:46642->192.168.8.109:53: i/o timeout
[ERROR] plugin/errors: 2 1898797220.1916943194. HINFO: read udp 10.42.0.38:55329->192.168.8.109:53: i/o timeout
[ERROR] plugin/errors: 2 1898797220.1916943194. HINFO: read udp 10.42.0.38:44471->192.168.8.109:53: i/o timeout
[ERROR] plugin/errors: 2 1898797220.1916943194. HINFO: read udp 10.42.0.38:49182->192.168.8.109:53: i/o timeout
[ERROR] plugin/errors: 2 1898797220.1916943194. HINFO: read udp 10.42.0.38:54082->192.168.8.109:53: i/o timeout
[ERROR] plugin/errors: 2 1898797220.1916943194. HINFO: read udp 10.42.0.38:48151->192.168.8.109:53: i/o timeout
[ERROR] plugin/errors: 2 1898797220.1916943194. HINFO: read udp 10.42.0.38:48599->192.168.8.109:53: i/o timeout
人们推荐的地方
- 更改 coredns 配置映射以转发到您的主节点 IP
... other CoreFile stuff
forward . host server IP
... other CoreFile stuff
- 或将您的 coredns clusterip IP 作为名称服务器添加到/etc/resolve.conf
search default.svc.cluster.local svc.cluster.local cluster.local
nameserver 10.42.0.38
nameserver 192.168.8.1
nameserver fe80::266:19ff:fea7:85e7%wlan0
，但是没有发现这些解决方案有效。
引用资料:
$ kubectl get nodes -o wide
NAME STATUS ROLES AGE VERSION INTERNAL-IP EXTERNAL-IP OS-IMAGE KERNEL-VERSION CONTAINER-RUNTIME
raspberrypi Ready master 153d v1.18.9+k3s1 192.168.8.109 <none> Raspbian GNU/Linux 10 (buster) 5.10.9-v7l+ containerd://1.3.3-k3s2
$ kubectl get svc -n kube-system -o wide
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
kube-dns ClusterIP 10.43.0.10 <none> 53/UDP,53/TCP,9153/TCP 153d k8s-app=kube-dns
metrics-server ClusterIP 10.43.205.8 <none> 443/TCP 153d k8s-app=metrics-server
traefik-prometheus ClusterIP 10.43.222.138 <none> 9100/TCP 153d app=traefik,release=traefik
traefik LoadBalancer 10.43.249.133 192.168.8.109 80:31222/TCP,443:32509/TCP 153d app=traefik,release=traefik
$ kubectl get ep kube-dns -n kube-system
NAME ENDPOINTS AGE
kube-dns 10.42.0.38:53,10.42.0.38:9153,10.42.0.38:53 153d
不知道我哪里出错了，或者我是否专注于错误的事情，或者如何继续。如有任何帮助，我们将不胜感激。
最佳答案
当所有其他方法都失败时......返回手册。我试图在所有错误的地方找到“问题”，而我只需要按照 Rancher 的 k3s 安装文档(叹气)。
Rancher's documentation非常好(你只需要真正遵循它)，他们说在 Raspbian Buster 环境
上安装 k3s 时check version:
$ lsb_release -a No LSB modules are available. Distributor ID: Raspbian Description: Raspbian GNU/Linux 10 (buster) Release: 10 Codename: buster
您需要更改为legacy iptables，声明运行 ( link ):
sudo iptables -F
sudo update-alternatives --set iptables /usr/sbin/iptables-legacy
sudo update-alternatives --set ip6tables /usr/sbin/ip6tables-legacy
sudo reboot
note that when setting the iptables, do it directly on the pi, not via ssh. You will be kicked out
这样做之后，我所有的服务都很满意，并且可以通过它们定义的 clusterIP 服务名称等从容器内相互 curl。
关于kubernetes - k3s - pod 之间的网络无法正常工作，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/66463181/