应该有不少人遇到过kubernetes只能以"http://127.0.0.1:8080"进行访问的问题，每个人的具体情况可能并不是完全一样，我在部署完单机版kubernetes之后，用"http://127.0.0.1:8080"能够访问kubernetes服务，但是用"http://ip:8080"却访问服务失败。具体情况如下：
[root@localhost ******]# curl http://127.0.0.1:8080      
{
  "paths": [
    "/api",
    "/api/v1",
    "/apis",
    "/apis/apps",
    "/apis/apps/v1beta1",
    "/apis/authentication.k8s.io",
    "/apis/authentication.k8s.io/v1beta1",
    "/apis/authorization.k8s.io",
    "/apis/authorization.k8s.io/v1beta1",
    "/apis/autoscaling",
    "/apis/autoscaling/v1",
    "/apis/batch",
    "/apis/batch/v1",
    "/apis/batch/v2alpha1",
    "/apis/certificates.k8s.io",
    "/apis/certificates.k8s.io/v1alpha1",
    "/apis/extensions",
    "/apis/extensions/v1beta1",
    "/apis/policy",
    "/apis/policy/v1beta1",
    "/apis/rbac.authorization.k8s.io",
    "/apis/rbac.authorization.k8s.io/v1alpha1",
    "/apis/storage.k8s.io",
    "/apis/storage.k8s.io/v1beta1",
    "/healthz",
    "/healthz/ping",
    "/healthz/poststarthook/bootstrap-controller",
    "/healthz/poststarthook/extensions/third-party-resources",
    "/healthz/poststarthook/rbac/bootstrap-roles",
    "/logs",
    "/metrics",
    "/swaggerapi/",
    "/ui/",
    "/version"
  ]
}
[root@localhost ******]#curl http://192.168.52.134:8080
curl: (7) Failed connect to 192.168.52.134:8080; 拒绝连接
        具体不知道什么原因，朋友给我推荐了一篇博文，但是这篇博文是以集群方式搭建的，和我自己的单机版不太一样，于是根据这篇博文的搭建过程进行尝试，最后总结发现只需要修改一个地方就够了，即将"/etc/kubernetes/apiserver"里面的'KUBE_API_ADDRESS="--insecure-bind-address=127.0.0.1"'改为'KUBE_API_ADDRESS="--insecure-bind-address=0.0.0.0"'就好了，然后别忘了重启"kube-apiserver"。
参考博文：https://www.cnblogs.com/zhenyuyaodidiao/p/6500830.html
修改文件：vim /etc/kubernetes/apiserver
将KUBE_API_ADDRESS="--insecure-bind-address=127.0.0.1"改为KUBE_API_ADDRESS="--insecure-bind-address=0.0.0.0"
重启命令：systemctl restart kube-apiserver
这一步千万不要忘了，要不然没生效，还以为是改错地方了。然后再试发现就可以用ip访问kubernetes服务了。
[root@localhost ******]#curl http://192.168.52.134:8080
{
  "paths": [
    "/api",
    "/api/v1",
    "/apis",
    "/apis/apps",
    "/apis/apps/v1beta1",
    "/apis/authentication.k8s.io",
    "/apis/authentication.k8s.io/v1beta1",
    "/apis/authorization.k8s.io",
    "/apis/authorization.k8s.io/v1beta1",
    "/apis/autoscaling",
    "/apis/autoscaling/v1",
    "/apis/batch",
    "/apis/batch/v1",
    "/apis/batch/v2alpha1",
    "/apis/certificates.k8s.io",
    "/apis/certificates.k8s.io/v1alpha1",
    "/apis/extensions",
    "/apis/extensions/v1beta1",
    "/apis/policy",
    "/apis/policy/v1beta1",
    "/apis/rbac.authorization.k8s.io",
    "/apis/rbac.authorization.k8s.io/v1alpha1",
    "/apis/storage.k8s.io",
    "/apis/storage.k8s.io/v1beta1",
    "/healthz",
    "/healthz/ping",
    "/healthz/poststarthook/bootstrap-controller",
    "/healthz/poststarthook/extensions/third-party-resources",
    "/healthz/poststarthook/rbac/bootstrap-roles",
    "/logs",
    "/metrics",
    "/swaggerapi/",
    "/ui/",
    "/version"
  ]
}
        遇到问题莫要慌，先自己找原因，不行再求助网络或者求助别人，正常情况下都会有现有的解决方案的，因为你遇到的大多数问题都是别人已经遇到过的问题，事后进行总结。踩一次坑就少一个坑，总结一下就前进一步。