Question

我在Kubernetes中将MongoDB ReplicaSet部署为StatefulSet。我正在运行Bare Metal K8S群集，因此我正在使用MetalLB公开LoadBalancer类型的服务。对于我的MongoDB-RS安装程序，公开的服务如下所示：

NAME              TYPE           CLUSTER-IP      EXTERNAL-IP     PORT(S)           AGE
mongo-0           LoadBalancer   10.43.199.127   172.16.24.151   27017:31118/TCP   55m
mongo-1           LoadBalancer   10.43.180.131   172.16.24.152   27017:31809/TCP   55m
mongo-2           LoadBalancer   10.43.156.124   172.16.24.153   27017:30312/TCP   55m

这可以按预期工作，但是从外部客户端连接到RS时出现问题：

➜  ~ mongo "mongodb://172.16.24.151:27017,172.16.24.152:27017,172.16.24.153:27017/?replicaSet=rs0"
MongoDB shell version v4.0.10
connecting to: mongodb://172.16.24.151:27017,172.16.24.152:27017,172.16.24.153:27017/?gssapiServiceName=mongodb&replicaSet=rs0
2019-07-05T10:47:27.058+0200 I NETWORK  [js] Starting new replica set monitor for rs0/172.16.24.151:27017,172.16.24.152:27017,172.16.24.153:27017
2019-07-05T10:47:27.106+0200 I NETWORK  [js] Successfully connected to 172.16.24.153:27017 (1 connections now open to 172.16.24.153:27017 with a 5 second timeout)
2019-07-05T10:47:27.106+0200 I NETWORK  [ReplicaSetMonitor-TaskExecutor] Successfully connected to 172.16.24.151:27017 (1 connections now open to 172.16.24.151:27017 with a 5 second timeout)
2019-07-05T10:47:27.136+0200 I NETWORK  [ReplicaSetMonitor-TaskExecutor] changing hosts to rs0/10.42.2.155:27017,10.42.3.147:27017,10.42.4.108:27017 from rs0/172.16.24.151:27017,172.16.24.152:27017,172.16.24.153:27017
2019-07-05T10:47:52.654+0200 W NETWORK  [js] Unable to reach primary for set rs0
2019-07-05T10:47:52.654+0200 I NETWORK  [js] Cannot reach any nodes for set rs0. Please check network connectivity and the status of the set. This has happened for 1 checks in a row.
2019-07-05T10:47:52.654+0200 E QUERY    [js] Error: connect failed to replica set rs0/172.16.24.151:27017,172.16.24.152:27017,172.16.24.153:27017 :
connect@src/mongo/shell/mongo.js:344:17

在某个时候它说“将主机更改为rs0 / 10.42.2.155：27017,10.42.3.147：27017,10.42.4.108：27017”。由于这些IP是群集内部的，因此此后连接将失败。

有什么建议我可以做什么？

Answer 1

您正在使用的负载均衡器不是不稳定的会话，您可以使用nginx控制器为基于nginx的负载平衡器提供基于客户端或cookie设置粘性会话亲和力的功能。

https://github.com/kubernetes/ingress-nginx

另一种选择是使用其他容器作为mongo代理，例如，您可以使用HAPoxy容器，在其中配置HAProxy来侦听27017端口上的TCP连接，并作为后端3种不同的mongo服务，其余仍需要设置HAProxy中的一个healtheck，可以使您知道尚有多少个后台程序。

公开和连接以K8S Statefulset运行的MongoDB ReplicaSet

1 个答案: