RousselTMLEARNING

FAQ

Frequently asked questions

Practical answers to help you prepare for your course and keep learning.

67 results Reset
What is the difference between Docker and a virtual machine?

Containers share the host OS kernel, so they are much lighter and faster.

Docker: From Discovery to Expertise ↗
Is this training suitable for beginners?

Yes, it starts with the basic concepts and evolves towards advanced orchestration.

Docker: From Discovery to Expertise ↗
What is a Dockerfile?

It is a text script containing instructions to build a Docker image.

Docker: From Discovery to Expertise ↗
What is Docker Compose?

A tool to define and run multi-container Docker applications.

Docker: From Discovery to Expertise ↗
What is Docker Hub?

It's a public registry where you can find and share Docker images.

Docker: From Discovery to Expertise ↗
What is Docker Swarm?

Docker's native tool to orchestrate a cluster of Docker engines.

Docker: From Discovery to Expertise ↗
Are my data lost if the container stops?

Yes, unless you use Docker volumes to persist data.

Docker: From Discovery to Expertise ↗
Why use multi-stage builds?

To reduce the final image size by excluding compilation tools.

Docker: From Discovery to Expertise ↗
Can we limit a container's resources?

Yes, you can impose CPU and RAM limits when starting it.

Docker: From Discovery to Expertise ↗
How does Docker integrate with Kubernetes?

Kubernetes uses standard containers (often Docker or containerd) for orchestration.

Docker: From Discovery to Expertise ↗
What is Dynatrace?

It is a complete observability platform based on artificial intelligence.

Dynatrace: From Discovery to Expertise ↗
What is the difference between SaaS and Managed?

SaaS is hosted by Dynatrace, Managed is installed on your own infrastructure.

Dynatrace: From Discovery to Expertise ↗
What is OneAgent?

A single agent that installs on your hosts to automatically collect all metrics and traces.

Dynatrace: From Discovery to Expertise ↗
How does Davis AI work?

Davis AI analyzes billions of dependencies to find the exact root cause of a problem.

Dynatrace: From Discovery to Expertise ↗
What is Grail?

Dynatrace's data lakehouse designed specifically for unified observability data.

Dynatrace: From Discovery to Expertise ↗
Can we monitor containers?

Yes, Dynatrace integrates perfectly with Docker, Kubernetes, and OpenShift.

Dynatrace: From Discovery to Expertise ↗
What is Monaco?

The 'Monitoring as Code' tool to manage your Dynatrace configurations as code.

Dynatrace: From Discovery to Expertise ↗
Can we simulate user journeys?

Yes, with synthetic monitors (Synthetic Monitoring).

Dynatrace: From Discovery to Expertise ↗
How to manage costs in Dynatrace?

Thanks to DDUs (Davis Data Units) which allow tracking the consumption of different metrics.

Dynatrace: From Discovery to Expertise ↗
Is there a certification?

Yes, there are several levels such as Associate, Advanced Observability, etc.

Dynatrace: From Discovery to Expertise ↗
What is Ansible?

It is an open-source automation tool for configuration management, application deployment, and orchestration of IT tasks.

Ansible: from discovery to expertise ↗
Does Ansible require an agent?

No, Ansible is 'agentless'. It communicates with remote servers via SSH (for Linux/Unix) or WinRM (for Windows).

Ansible: from discovery to expertise ↗
What is an Ansible playbook?

It is a YAML formatted file that describes a set of ordered tasks to be executed on one or more target servers (the inventory).

Ansible: from discovery to expertise ↗
What is Logstash?

An open source data collection engine to process and enrich events.

Logstash: from discovery to expertise ↗
What is a pipeline?

A series of data processing steps including inputs, filters, and outputs.

Logstash: from discovery to expertise ↗
Why use the Grok filter?

To parse and structure unstructured text into identifiable fields.

Logstash: from discovery to expertise ↗
What is the difference between Beats and Logstash?

Beats is lightweight and collects data at the source, while Logstash is a heavy engine that centralizes and transforms the data.

Logstash: from discovery to expertise ↗
Qu'est-ce que Prometheus ?

Un système de supervision et d'alerting open source spécialisé dans les séries temporelles.

Prometheus : de la découverte à l'expertise ↗
Quelle est son architecture de base ?

Il utilise un modèle 'pull' où le serveur vient récupérer les métriques sur les cibles.

Prometheus : de la découverte à l'expertise ↗
Qu'est-ce qu'un Exporter ?

Un agent qui traduit des métriques tierces au format compris par Prometheus.

Prometheus : de la découverte à l'expertise ↗
C'est quoi PromQL ?

Le langage d'interrogation puissant permettant de manipuler les séries temporelles.

Prometheus : de la découverte à l'expertise ↗
Comment surveiller un script court ?

En utilisant Pushgateway, car le modèle 'pull' n'est pas adapté pour les tâches très courtes.

Prometheus : de la découverte à l'expertise ↗
Prometheus remplace-t-il Logstash ?

Non, Prometheus gère uniquement les métriques. Logstash gère les logs.

Prometheus : de la découverte à l'expertise ↗
Comment gérer les alertes ?

Prometheus évalue les règles d'alerte et envoie les événements à Alertmanager.

Prometheus : de la découverte à l'expertise ↗
Qu'est-ce que cAdvisor ?

Un outil pour collecter les métriques d'utilisation des conteneurs Docker/Kubernetes.

Prometheus : de la découverte à l'expertise ↗
Peut-on l'intégrer avec Grafana ?

Oui, Prometheus est la source de données par défaut et la plus utilisée pour Grafana.

Prometheus : de la découverte à l'expertise ↗
Est-ce adapté pour les environnements dynamiques ?

Oui, il intègre des mécanismes de découverte de services (Service Discovery).

Prometheus : de la découverte à l'expertise ↗
What is Cloud Computing?

It is the on-demand access, via the Internet, to shared computing resources (servers, storage, applications) with a pay-as-you-go model.

Cloud Computing: From Discovery to Expertise ↗
What is the difference between IaaS, PaaS, and SaaS?

IaaS provides the core infrastructure, PaaS offers a platform for developers, and SaaS provides finished software accessible via a browser.

Cloud Computing: From Discovery to Expertise ↗
What is elasticity?

It is the ability of a Cloud infrastructure to automatically increase or decrease its resources to adapt to the load in real time.

Cloud Computing: From Discovery to Expertise ↗
Qu'est-ce que Grafana ?

C'est une plateforme open source de visualisation et d'analyse de métriques.

Grafana : de la découverte à l'expertise ↗
Quelles sources de données sont supportées ?

Grafana supporte de nombreuses sources comme Prometheus, Elasticsearch, InfluxDB, MySQL, PostgreSQL, etc.

Grafana : de la découverte à l'expertise ↗
Quelle est la différence entre Grafana et Kibana ?

Kibana est très lié à Elasticsearch pour les logs, Grafana est plus agnostique et excelle dans les métriques et l'intégration multi-sources.

Grafana : de la découverte à l'expertise ↗
Peut-on configurer des alertes ?

Oui, Grafana dispose d'un système d'alerting puissant intégré.

Grafana : de la découverte à l'expertise ↗
Comment sécuriser Grafana ?

Via l'authentification (LDAP, OAuth), le HTTPS et la gestion fine des permissions par dossier et tableau de bord.

Grafana : de la découverte à l'expertise ↗
Qu'est-ce qu'une variable de tableau de bord ?

Elle permet de rendre les tableaux de bord dynamiques (ex: filtrer par serveur ou environnement).

Grafana : de la découverte à l'expertise ↗
Peut-on exporter des tableaux de bord ?

Oui, au format JSON pour les sauvegarder ou les partager.

Grafana : de la découverte à l'expertise ↗
Grafana Cloud ou auto-hébergé ?

Grafana Cloud est un service SaaS managé, l'auto-hébergement vous donne le contrôle total sur l'infrastructure.

Grafana : de la découverte à l'expertise ↗
Que sont les annotations ?

Des marqueurs visuels sur les graphiques pour indiquer des événements (déploiements, pannes).

Grafana : de la découverte à l'expertise ↗
Est-il possible d'utiliser Grafana pour les logs ?

Oui, notamment avec Loki, la solution de logs intégrée à l'écosystème Grafana.

Grafana : de la découverte à l'expertise ↗
What are Beats?

They are lightweight agents from the Elastic stack installed on servers to collect data.

Beats: From Discovery to Expertise ↗
Filebeat vs Logstash?

Filebeat collects and sends logs in a lightweight way, while Logstash is a heavy transformation engine.

Beats: From Discovery to Expertise ↗
What is Metricbeat?

An agent dedicated to collecting system and service metrics.

Beats: From Discovery to Expertise ↗
Beats or Elastic Agent?

Elastic Agent is the new unified solution intended to replace individual Beats.

Beats: From Discovery to Expertise ↗
What is Fleet?

The centralized interface in Kibana for configuring and updating Elastic Agents at scale.

Beats: From Discovery to Expertise ↗
Do they work on Windows?

Yes, Winlogbeat is specifically designed for Windows event logs.

Beats: From Discovery to Expertise ↗
Where do they send the data?

Mainly to Elasticsearch or Logstash, but also to Kafka or Redis.

Beats: From Discovery to Expertise ↗
Do they consume a lot of resources?

No, they are written in Go and designed to be very lightweight.

Beats: From Discovery to Expertise ↗
What are modules?

Ready-to-use configurations for common systems (Nginx, MySQL) including dashboards.

Beats: From Discovery to Expertise ↗
Is the transport secure?

Yes, they support SSL/TLS encryption and authentication.

Beats: From Discovery to Expertise ↗
What is Kubernetes (K8s)?

It is an open-source container orchestration system that automates deployment, scaling, and management of containerized applications.

Kubernetes: From Discovery to Expertise ↗
What is the difference between a Pod and a Deployment?

A Pod is the smallest deployable unit in Kubernetes, containing one or more containers. A Deployment is a higher-level object that manages ReplicaSets, which in turn ensure that a specific number of identical Pods are running at all times.

Kubernetes: From Discovery to Expertise ↗
What is a Service in Kubernetes?

It is an abstraction that defines a logical set of Pods and a policy to access them (via a stable IP and port), acting as an entry point and internal load balancer.

Kubernetes: From Discovery to Expertise ↗
What is Grafana Alloy?

It is an open-source, vendor-neutral telemetry collector designed to replace Grafana Agent. It is OpenTelemetry (OTel) compatible.

Alloy: From Discovery to Expertise ↗
Does Alloy replace Promtail and other agents?

Yes, Alloy combines the features of Promtail and Grafana Agent and includes native support for OpenTelemetry.

Alloy: From Discovery to Expertise ↗
What configuration language does Alloy use?

Alloy uses a declarative syntax based on River (similar to Terraform's HCL) which simplifies pipeline creation.

Alloy: From Discovery to Expertise ↗
Can Alloy be used for OpenTelemetry?

Absolutely, Alloy offers full native support for receiving, processing, and exporting data (Traces, Logs, Metrics) via the OTLP protocol.

Alloy: From Discovery to Expertise ↗