我正在尝试在Kubernetes Google Cloud集群上运行我的Django + PostgreSQL应用程序。我已成功部署以下文件：
但是我在将PostgreSQL数据库部署到集群时遇到了麻烦。这是我的.yml文件的定义：
apiVersion: v1
kind: Service
metadata:
name: postgres-service
spec:
selector:
app: postgres-container
tier: backend
ports:
- protocol: TCP
port: 5432
targetPort: 5432
type: ClusterIP
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: postgres-pvc
labels:
type: local
spec:
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 2Gi
---
apiVersion: apps/v1beta2
kind: Deployment
metadata:
name: postgres
spec:
replicas: 1
selector:
matchLabels:
app: postgres-container
tier: backend
template:
metadata:
labels:
app: postgres-container
tier: backend
spec:
containers:
- name: postgres-container
image: postgres:9.6.6
env:
- name: POSTGRES_USER
valueFrom:
secretKeyRef:
name: postgres-credentials
key: user
- name: POSTGRES_PASSWORD
valueFrom:
secretKeyRef:
name: postgres-credentials
key: password
- name: POSTGRES_DB
value: agent_technologies_db
ports:
- containerPort: 5432
volumeMounts:
- name: postgres-volume-mount
mountPath: /var/lib/postgresql/data
volumes:
- name: postgres-volume-mount
persistentVolumeClaim:
claimName: postgres-pvc
- name: postgres-credentials
secret:
secretName: postgres-credentials
这是我运行kubectl logs postgres-85c56dfb9b-95c74命令时出现的错误：
initdb: directory "/var/lib/postgresql/data" exists but is not empty
It contains a lost+found directory, perhaps due to it being a mount point.
Using a mount point directly as the data directory is not recommended.
Create a subdirectory under the mount point.
The files belonging to this database system will be owned by user "postgres".
This user must also own the server process.
The database cluster will be initialized with locale "en_US.utf8".
The default database encoding has accordingly been set to "UTF8".
The default text search configuration will be set to "english".
有人可以向我解释这个错误。提前谢谢！
***** UPDATE ******
当我运行kubectl logs $pod时，我收到以下错误（即使容器在群集上正在运行）：
Host: 10.52.1.5
Production - Using "POSTGRESQL" Database
/usr/local/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>.
""")
Host: 10.52.1.5
Production - Using "POSTGRESQL" Database
/usr/local/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 0x7f62f4c948c8>
Traceback (most recent call last):
File "/usr/local/lib/python3.6/site-packages/django/db/backends/base/base.py", line 216, in ensure_connection
self.connect()
File "/usr/local/lib/python3.6/site-packages/django/db/backends/base/base.py", line 194, in connect
self.connection = self.get_new_connection(conn_params)
File "/usr/local/lib/python3.6/site-packages/django/db/backends/postgresql/base.py", line 168, in get_new_connection
connection = Database.connect(**conn_params)
File "/usr/local/lib/python3.6/site-packages/psycopg2/__init__.py", line 130, in connect
conn = _connect(dsn, connection_factory=connection_factory, **kwasync)
psycopg2.OperationalError: could not connect to server: No such file or directory
Is the server running locally and accepting
connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"?
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "/usr/local/lib/python3.6/site-packages/django/utils/autoreload.py", line 225, in wrapper
fn(*args, **kwargs)
File "/usr/local/lib/python3.6/site-packages/django/core/management/commands/runserver.py", line 124, in inner_run
self.check_migrations()
File "/usr/local/lib/python3.6/site-packages/django/core/management/base.py", line 427, in check_migrations
executor = MigrationExecutor(connections[DEFAULT_DB_ALIAS])
File "/usr/local/lib/python3.6/site-packages/django/db/migrations/executor.py", line 18, in __init__
self.loader = MigrationLoader(self.connection)
File "/usr/local/lib/python3.6/site-packages/django/db/migrations/loader.py", line 49, in __init__
self.build_graph()
File "/usr/local/lib/python3.6/site-packages/django/db/migrations/loader.py", line 206, in build_graph
self.applied_migrations = recorder.applied_migrations()
File "/usr/local/lib/python3.6/site-packages/django/db/migrations/recorder.py", line 61, in applied_migrations
if self.has_table():
File "/usr/local/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 "/usr/local/lib/python3.6/site-packages/django/db/backends/base/base.py", line 255, in cursor
return self._cursor()
File "/usr/local/lib/python3.6/site-packages/django/db/backends/base/base.py", line 232, in _cursor
self.ensure_connection()
File "/usr/local/lib/python3.6/site-packages/django/db/backends/base/base.py", line 216, in ensure_connection
self.connect()
File "/usr/local/lib/python3.6/site-packages/django/db/utils.py", line 89, in __exit__
raise dj_exc_value.with_traceback(traceback) from exc_value
File "/usr/local/lib/python3.6/site-packages/django/db/backends/base/base.py", line 216, in ensure_connection
self.connect()
File "/usr/local/lib/python3.6/site-packages/django/db/backends/base/base.py", line 194, in connect
self.connection = self.get_new_connection(conn_params)
File "/usr/local/lib/python3.6/site-packages/django/db/backends/postgresql/base.py", line 168, in get_new_connection
connection = Database.connect(**conn_params)
File "/usr/local/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 connect to server: No such file or directory
Is the server running locally and accepting
connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"?
这是来自我的settings.py文件：
import socket
print("Host: "+socket.gethostbyname(socket.gethostname()))
if(os.getenv('POSTGRES_DB_HOST')==None):
print('Development - Using "SQLITE3" Database')
DATABASES = {
'default':{
'ENGINE': 'django.db.backends.sqlite3',
'NAME': os.path.join(BASE_DIR,'db.sqlite3'),
}
}
else:
print('Production - Using "POSTGRESQL" Database')
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.postgresql_psycopg2',
'NAME': 'agent_technologies_db',
'USER': 'stefan_radonjic',
'PASSWORD': 'cepajecar995',
'HOST': os.getenv('POSTGRES_HOST'),
'PORT': os.getenv('POSTGRES_PORT'),
}
}
当我运行kubectl logs $pod命令时，我得到的错误可能是因为PostgreSQL contianer没有运行而无法找到它或者？如果有人对我项目的其他文件感兴趣，请访问github链接：https://github.com/StefanCepa/agent-technologies-bachelor
答案 0 :(得分：1)
对我来说这看起来不是一个错误，更像是一个警告。 PostgreSQL抱怨你应该为Postgres数据文件夹使用一个完全空的目录。应用程序告诉您要做的是在卷内创建一个空目录，并在该特定子目录中创建。这可以通过以下方式完成：
在卷中创建一个子目录，您可以使用例如一个安装卷的initContainer并创建目录。
现在您有一个创建目录的卷，然后您可以修改Postgres中的postgres-volume-mount并将subPath添加到新创建的目录中。
- name: postgres-volume-mount
mountPath: /var/lib/postgresql/data
subPath: NAME_OF_YOUR_SUBDIRECTORY