尝试使用PostgreSQL DB部署Dockerized Django应用程序时，Kubernetes Pod对象在无限循环中崩溃

Question

我正在研究我的Django项目，我正在尝试将其部署在Kubernetes集群（Google Cloud Provider）上。我已经设法创建了配置集群所需的所有文件：

• Django App部署+服务.yml文件
• Postgres数据库部署+服务+ PersistentVolumeClaim（动态创建PersistentVolume对象并使用PD存储 默认情况下为云节点）+ Secret .yml文件
• Docker文件+ Docker撰写（我对docker没有太多经验，所以可能有些问题，也许就是 问题，但我无法弄明白）

出于某种原因，当我尝试应用它们时，我的POD，特别是Django应用程序POD，在无限循环中崩溃。我的Postgres Pod也没有崩溃，但它没有运行。

任何人都可以帮我弄清楚我做错了什么吗？这是我的github回购：https://github.com/…/mast…/agents/config/kubernetes/postgres

我最好的猜测是我没有在DATABASES文件中设置settings.py配置正确，而且我的Django应用程序找不到settings.py中指定的DATABASE HOST。如果有人有任何建议请发表评论。

以下是我的Kubernetes Pod列表的图片：

这是我描述第一个Pod对象的图片：

这是我描述的一个节点的图片：

*更新*

以下是我尝试运行python src/manage.py runserver时的错误消息：

(web_development) cepa995@cepa995-VirtualBox:~/Agentske_Tehnologije/agents$ python src/manage.py runserver
/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/psycopg2/__init__.py:144: UserWarning: The psycopg2 wheel package will be renamed from release 2.8; in order to keep installing from binary please use "pip install psycopg2-binary" instead. For details see: <http://initd.org/psycopg/docs/install.html#binary-install-from-pypi>.
  """)
/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/psycopg2/__init__.py:144: UserWarning: The psycopg2 wheel package will be renamed from release 2.8; in order to keep installing from binary please use "pip install psycopg2-binary" instead. For details see: <http://initd.org/psycopg/docs/install.html#binary-install-from-pypi>.
  """)
Performing system checks...

System check identified no issues (0 silenced).
Unhandled exception in thread started by <function check_errors.<locals>.wrapper at 0x7f6b37e9a9d8>
Traceback (most recent call last):
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/django/db/backends/base/base.py", line 216, in ensure_connection
    self.connect()
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/django/db/backends/base/base.py", line 194, in connect
    self.connection = self.get_new_connection(conn_params)
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/django/db/backends/postgresql/base.py", line 168, in get_new_connection
    connection = Database.connect(**conn_params)
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/psycopg2/__init__.py", line 130, in connect
    conn = _connect(dsn, connection_factory=connection_factory, **kwasync)
psycopg2.OperationalError: could not translate host name "postgres-service" to address: Name or service not known


The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/django/utils/autoreload.py", line 225, in wrapper
    fn(*args, **kwargs)
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/django/core/management/commands/runserver.py", line 124, in inner_run
    self.check_migrations()
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/django/core/management/base.py", line 427, in check_migrations
    executor = MigrationExecutor(connections[DEFAULT_DB_ALIAS])
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/django/db/migrations/executor.py", line 18, in __init__
    self.loader = MigrationLoader(self.connection)
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/django/db/migrations/loader.py", line 49, in __init__
    self.build_graph()
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/django/db/migrations/loader.py", line 206, in build_graph
    self.applied_migrations = recorder.applied_migrations()
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/django/db/migrations/recorder.py", line 61, in applied_migrations
    if self.has_table():
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/django/db/migrations/recorder.py", line 44, in has_table
    return self.Migration._meta.db_table in self.connection.introspection.table_names(self.connection.cursor())
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/django/db/backends/base/base.py", line 255, in cursor
    return self._cursor()
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/django/db/backends/base/base.py", line 232, in _cursor
    self.ensure_connection()
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/django/db/backends/base/base.py", line 216, in ensure_connection
    self.connect()
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/django/db/utils.py", line 89, in __exit__
    raise dj_exc_value.with_traceback(traceback) from exc_value
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/django/db/backends/base/base.py", line 216, in ensure_connection
    self.connect()
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/django/db/backends/base/base.py", line 194, in connect
    self.connection = self.get_new_connection(conn_params)
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/django/db/backends/postgresql/base.py", line 168, in get_new_connection
    connection = Database.connect(**conn_params)
  File "/home/cepa995/anaconda3/envs/web_development/lib/python3.6/site-packages/psycopg2/__init__.py", line 130, in connect
    conn = _connect(dsn, connection_factory=connection_factory, **kwasync)
django.db.utils.OperationalError: could not translate host name "postgres-service" to address: Name or service not known

Answer 1

您的应用程序无法连接到数据库，因为您的Postgres服务器无法启动（您在Ready状态下有0/1 pod）。

你没有发布它的Pod事件，但我猜主要原因是它的音量。

在你的Postgres规范中，我看到你将音量类型设置为 ReadWriteMany，但Google Cloud不提供具有该类型的卷（documentation，路径“访问模式”），实际上，我没有看到您需要它的原因。将类型更改为ReadWriteOnce并重新部署数据库，它应该有所帮助。

P.S。要在群集中获取应用程序日志，可以调用kubectl logs $podname，这样会更有帮助 P.P.S.当您发布文本信息时，请使用文本格式。