请求协助：Promtail无法向Grafana Cloud Loki推送日志

问题情况 #

Promtail已主动监控日志文件/app/logs/auth-app.log，能正确定位文件偏移量并启动追踪，日志中无报错信息，运行状态看似正常，但始终未出现“Pushing logs to client”的日志消息，说明日志未成功推送至Grafana Cloud Loki。

Promtail输出日志 #

(base) mac@macs-MacBook-Pro auth % docker logs -f auth-promtail-1

    level=info ts=2025-01-14T03:10:07.588750965Z caller=filetarget.go:313 msg="watching new directory" directory=/app/logs
    
    level=info ts=2025-01-14T03:10:07.589300673Z caller=tailer.go:145 component=tailer msg="tail routine: started" path=/app/logs/auth-app.log
    
    ts=2025-01-14T03:10:07.589470006Z caller=log.go:168 level=info msg="Seeked /app/logs/auth-app.log - &{Offset:0 Whence:0}"
    
    level=info ts=2025-01-14T03:21:21.096513388Z caller=promtail.go:133 msg="Reloading configuration file" md5sum=294099248eea1cf971a3bf2241440903
    
    level=info ts=2025-01-14T03:21:21.096935596Z caller=server.go:322 http=[::]:9080 grpc=[::]:42413 msg="server listening on addresses"
    
    level=info ts=2025-01-14T03:21:21.097025804Z caller=main.go:174 msg="Starting Promtail" version="(version=2.9.0, branch=HEAD, revision=2feb64f69)"
    
    level=warn ts=2025-01-14T03:21:21.097066054Z caller=promtail.go:263 msg="enable watchConfig"
    
    level=info ts=2025-01-14T03:21:26.097119626Z caller=filetargetmanager.go:361 msg="Adding target" key="/app/logs/*.log:{job=\"auth-app\"}"
    
    level=info ts=2025-01-14T03:21:26.098878917Z caller=filetarget.go:313 msg="watching new directory" directory=/app/logs
    
    ts=2025-01-14T03:21:26.099545084Z caller=log.go:168 level=info msg="Seeked /app/logs/auth-app.log - &{Offset:4736 Whence:0}"
    
    level=info ts=2025-01-14T03:21:26.099664917Z caller=tailer.go:145 component=tailer msg="tail routine: started" path=/app/logs/auth-app.log
    
    level=info ts=2025-01-14T03:35:24.475875Z caller=promtail.go:133 msg="Reloading configuration file" md5sum=7331a19877f822e2c711f2885fce6122
    
    level=info ts=2025-01-14T03:35:24.476300708Z caller=server.go:322 http=[::]:9080 grpc=[::]:39125 msg="server listening on addresses"
    
    level=info ts=2025-01-14T03:35:24.476405916Z caller=main.go:174 msg="Starting Promtail" version="(version=2.9.0, branch=HEAD, revision=2feb64f69)"
    
    level=warn ts=2025-01-14T03:35:24.476431875Z caller=promtail.go:263 msg="enable watchConfig"
    
    level=info ts=2025-01-14T03:35:29.478968002Z caller=filetargetmanager.go:361 msg="Adding target" key="/app/logs/*.log:{app=\"auth-app\", env=\"dev\", job=\"auth-app\"}"
    
    level=info ts=2025-01-14T03:35:29.481305002Z caller=filetarget.go:313 msg="watching new directory" directory=/app/logs
    
    level=info ts=2025-01-14T03:35:29.482047419Z caller=tailer.go:145 component=tailer msg="tail routine: started" path=/app/logs/auth-app.log
    
    ts=2025-01-14T03:35:29.482108836Z caller=log.go:168 level=info msg="Seeked /app/logs/auth-app.log - &{Offset:4948 Whence:0}"

连通性测试结果 #

已验证Promtail到Grafana Cloud的连通性，结果正常：

mac@macs-MacBook-Pro auth % curl -u "{USERNAME}:{API KEY}" https://logs-prod-028.grafana.net

OK%

相关配置文件 #

docker-compose.yaml

services:
  auth-app:
    image: auth-app:latest
    # container_name: auth-app
    build: .
    ports:
      - "8080:8080"
    volumes:
      - ./logs:/app/logs  # Mount logs directory
    environment:
      - SPRING_DATASOURCE_URL=jdbc:mysql://mysql:3306/{database}
      - SPRING_DATASOURCE_USERNAME={XXX}
      - SPRING_DATASOURCE_PASSWORD={XXX}
      - SPRING_PROFILES_ACTIVE=dev
      - JAVA_OPTS=-Dlogging.config=classpath:logback-spring.xml
    depends_on:
      - mysql

  mysql:
    image: mysql:8.0
    container_name: mysql
    ports:
      - "3306:3306"
    environment:
      - MYSQL_ROOT_PASSWORD={XXX}
      - MYSQL_DATABASE={XXX}
    volumes:
      - db_data:/var/lib/mysql

  promtail:
    image: grafana/promtail:2.9.0
    volumes:
      - ./logs:/app/logs
      - ./promtail-config.yaml:/etc/promtail/config.yml
    command: -config.file=/etc/promtail/config.yml

volumes:
  db_data:

promtail-config.yaml

server:
  http_listen_port: 9080
  grpc_listen_port: 0

positions:
  filename: /tmp/positions.yaml

clients:
  - url: https://logs-prod-028.grafana.net/loki/api/v1/push
    basic_auth:
      username: {USERNAME}
      password: {API_KEY}


scrape_configs:
- job_name: auth-app
  static_configs:
  - targets:
      - localhost
    labels:
      job: auth-app
      env: dev
      app: auth-app
      __path__: /app/logs/*.log

内容的提问来源于stack exchange，提问作者mesh