Bits of .NET

📋 Container Logs = Debugging Power

Containers fail silently. Container logs reveal everything. Debug, monitor, track problems.

📝 Log Commands

# Show logs
docker logs container_name

# Follow logs (real-time)
docker logs -f container_name

# Last N lines
docker logs --tail 100 container_name

# With timestamps
docker logs -t container_name

# Since specific time
docker logs --since 2024-01-15T10:00:00 container_name

# Until specific time
docker logs --until 2024-01-15T11:00:00 container_name

# Follow with tail
docker logs -f --tail 50 container_name

# All containers logs
docker compose logs
docker compose logs -f
docker compose logs service_name

🎯 Logging Drivers

# json-file (default)
docker run --log-driver json-file --log-opt max-size=10m --log-opt max-file=3 app

# syslog
docker run --log-driver syslog --log-opt syslog-address=tcp://192.168.1.100:514 app

# journald
docker run --log-driver journald app

# fluentd
docker run --log-driver fluentd --log-opt fluentd-address=fluentd:24224 app

# awslogs
docker run --log-driver awslogs --log-opt awslogs-region=us-east-1 --log-opt awslogs-group=my-group app

# gelf (Graylog)
docker run --log-driver gelf --log-opt gelf-address=udp://graylog:12201 app

# none (no logs)
docker run --log-driver none app

✅ Debugging Tips

• Use -f for real-time monitoring
• Use –tail for recent logs
• Set log limits (max-size, max-file)
• Use structured logging (JSON)
• Centralize logs for production