kubernetes - 主机名未在命名空间中注册

问题描述

我已经通过 Rancher 设置了 Kuberbetes 集群。一切看起来都很好，直到我决定将 Helm Chart 应用程序部署到它（bitnami/wordpress）。

命名空间中的 Pod 和服务wordpress：

> kubectl get pods,svc -owide --namespace=wordpress
    NAME                             READY   STATUS    RESTARTS   AGE    IP           NODE            NOMINATED NODE   READINESS GATES
    pod/wordpress-6647794f9b-4mmxd   0/1     Running   20         104m   10.42.0.19   dev-app   <none>           <none>
    pod/wordpress-mariadb-0          1/1     Running   1          26h    10.42.0.14   dev-app   <none>           <none>
    
    NAME                        TYPE           CLUSTER-IP      EXTERNAL-IP   PORT(S)                      AGE   SELECTOR
    service/wordpress           LoadBalancer   10.43.91.13     <pending>     80:30158/TCP,443:30453/TCP   26h   app.kubernetes.io/instance=wordpress,app.kubernetes.io/name=wordpress,io.cattle.field/appId=wordpress
    service/wordpress-mariadb   ClusterIP      10.43.178.123   <none>        3306/TCP                     26h   app=mariadb,component=master,io.cattle.field/appId=wordpress,release=wordpress

然后我尝试验证从 Wordpress CMS 到 MariaDB 的连接：

在 MariaDB pod 上：

I have no name!@wordpress-mariadb-0:/$ cat /etc/hosts                                                      
# Kubernetes-managed hosts file.
127.0.0.1       localhost
::1     localhost ip6-localhost ip6-loopback
fe00::0 ip6-localnet
fe00::0 ip6-mcastprefix
fe00::1 ip6-allnodes
fe00::2 ip6-allrouters
10.42.0.14      wordpress-mariadb-0.wordpress-mariadb.wordpress.svc.cluster.local       wordpress-mariadb-0

不知道为什么-0要添加到主机名中，但是

I have no name!@wordpress-mariadb-0:/$ mysql -h wordpress-mariadb-0.wordpress-mariadb.wordpress.svc.cluster.local -u root -p                   
Enter password: 
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 48253
Server version: 10.3.22-MariaDB Source distribution

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MariaDB [(none)]>

从 MariaDB pod 可以正常工作。

比在 Wordpress pod 上：

I have no name!@wordpress-6647794f9b-4mmxd:/$ mysql -h wordpress-mariadb-0.wordpress-mariadb.wordpress.svc.cluster.local -u root -p
Enter password: 
ERROR 2005 (HY000): Unknown MySQL server host 'wordpress-mariadb-0.wordpress-mariadb.wordpress.svc.cluster.local' (-3)

由于某种原因，主机名没有为该命名空间注册。

有什么线索吗？

附言

从 wordpress 吊舱：

I have no name!@wordpress-6647794f9b-4mmxd:/$ cat /etc/hosts
# Kubernetes-managed hosts file.
127.0.0.1       localhost
::1     localhost ip6-localhost ip6-loopback
fe00::0 ip6-localnet
fe00::0 ip6-mcastprefix
fe00::1 ip6-allnodes
fe00::2 ip6-allrouters
10.42.0.19      wordpress-6647794f9b-4mmxd

# Entries added by HostAliases.
127.0.0.1       status.localhost

和

I have no name!@wordpress-6647794f9b-4mmxd:/$ cat /etc/resolv.conf 
nameserver 10.43.0.10
search wordpress.svc.cluster.local svc.cluster.local cluster.local
options ndots:5

PS2

> kubectl get pod -n kube-system
NAME                                      READY   STATUS      RESTARTS   AGE
canal-8bf2l                               2/2     Running     0          16d
canal-g782s                               2/2     Running     2          16d
canal-vq474                               2/2     Running     0          16d
coredns-849545576b-gcf7p                  1/1     Running     0          16d
coredns-849545576b-vtqpw                  1/1     Running     0          3d20h
coredns-autoscaler-84bf756579-v594n       1/1     Running     0          3d20h
metrics-server-697746ff48-rtw2h           1/1     Running     1          16d
rke-coredns-addon-deploy-job-2sjlv        0/1     Completed   0          3d20h
rke-ingress-controller-deploy-job-9q4c2   0/1     Completed   0          3d20h
rke-metrics-addon-deploy-job-cv42h        0/1     Completed   0          3d20h
rke-network-plugin-deploy-job-4pddn       0/1     Completed   0          3d20h

标签： kuberneteskubernetes-helmkubernetes-pod

kubernetes - 主机名未在命名空间中注册

问题描述

解决方案

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