python - mongodb 连接字符串 uri 在 Kubernetes 中不起作用

Question

我已在 K8S 上将 mongodb 部署为 StatefulSet。当我尝试使用连接字符串 URI(例如:mongodb://mongo-0.mongo:27017,mongo-1.mongo:27017/cool_db)连接数据库时，它没有连接，但它正在连接并获取结果当我使用端点 IP 地址时。

# kubectl get sts
NAME    READY   AGE
mongo   2/2     7h33m

#kubectl get pods
NAME                                      READY   STATUS    RESTARTS   AGE
mongo-0                                   2/2     Running   0          7h48m
mongo-1                                   2/2     Running   2          7h47m

# kubectl get svc
NAME         TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)     AGE
kubernetes   ClusterIP   10.96.0.1    <none>        443/TCP     10h
mongo        ClusterIP   None         <none>        27017/TCP   7h48m

我尝试使用以下过程在 python 中使用连接字符串 URI 来测试连接，但失败了。

>>> import pymongo
>>> client = pymongo.MongoClient("mongodb://mongo-0.mongo:27017,mongo-1.mongo:27017/cool_db")
>>> db = client.cool_db
>>> print db.cool_collection.count()
Traceback (most recent call last):
 File "<stdin>", line 1, in <module>
 File "/usr/lib64/python2.7/site-packages/pymongo/collection.py", line 1800, in count
   return self._count(cmd, collation, session)
 File "/usr/lib64/python2.7/site-packages/pymongo/collection.py", line 1600, in _count
   _cmd, self._read_preference_for(session), session)
 File "/usr/lib64/python2.7/site-packages/pymongo/mongo_client.py", line 1454, in _retryable_read
   read_pref, session, address=address)
 File "/usr/lib64/python2.7/site-packages/pymongo/mongo_client.py", line 1253, in _select_server
   server = topology.select_server(server_selector)
 File "/usr/lib64/python2.7/site-packages/pymongo/topology.py", line 235, in select_server
   address))
 File "/usr/lib64/python2.7/site-packages/pymongo/topology.py", line 193, in select_servers
   selector, server_timeout, address)
 File "/usr/lib64/python2.7/site-packages/pymongo/topology.py", line 209, in _select_servers_loop
   self._error_message(selector))
pymongo.errors.ServerSelectionTimeoutError: mongo-0.mongo:27017: [Errno -2] Name or service not known,mongo-1.mongo:27017: [Errno -2] Name or service not known

如果我们使用端点IP地址，那么我们将从数据库得到响应。

>>> import pymongo
>>> client = pymongo.MongoClient("mongodb://10.244.1.8,10.244.2.9:27017/cool_db")
>>> db = client.cool_db
>>> print db.cool_collection.count()
0
>>> 

我尝试过不同的URI，例如 (client = pymongo.MongoClient("mongodb://mongo-0.mongo:27017/cool_db") )，但不起作用。有人可以帮我吗？

Answer 1

来自my previous similar answer :

在集群内，您应该使用 <service-name>.<namespace-name>.svc.cluster.local 引用 MongoDB Pod .