LoopyLuci Docker Monitoring & Logs
Monitoring containers and collecting logs.
Live Monitoring
docker stats # live CPU/memory/IO
docker stats --no-stream # single snapshot
docker top myapp # processes inside
docker events --since 5m # events in last 5 min
Logs
docker logs --tail 100 -f myapp
docker logs --since 2024-01-01 myapp
docker logs myapp 2>&1 > out.txt
Log Drivers
x-logging: &log
driver: "json-file"
options: { max-size: "10m", max-file: "3" }
Prometheus
services:
prometheus: { image: prom/prometheus, ports: ["9090:9090"] }
cadvisor:
image: gcr.io/cadvisor/cadvisor:latest
volumes: [/:/rootfs:ro, /var/run:/var/run:ro]
ports: ["8080:8080"]
Aggregation
foreach ($id in (docker ps -q)) {
$name = docker inspect --format '{{.Name}}' $id
docker logs $id > "logs_$name.txt" 2>&1
}
Pitfalls
- json-file driver fills disk -- always set max-size/max-file
- docker logs only works with json-file or journald drivers
- docker events doesn't persist across restarts