Kostenlos · ohne Anmeldung · ohne Zeitlimit
Fertige Multiple-Choice-Übungsquizze, von Hand geprüft. Löse jedes Gratis-Quiz online — jede Antwort kommt mit Erklärung, und jede Quiz-Seite hat einen vollständigen Lösungsschlüssel zum Wiederholen.
IT
Deepen your technical knowledge of Linux namespaces, cgroups, Kubernetes control plane internals, CNI, and CRI. Beantworte jede Frage und sieh sofort, ob du richtig liegst — jedes Mal mit Erklärung.
Ein kostenloser Multiple-Choice-Übungstest mit 16 Fragen zu IT. Jede Frage hat eine richtige Antwort und eine kurze Erklärung, und der vollständige Lösungsschlüssel unter dem Quiz dient zugleich als Lernzettel. Kein Konto, kein Zeitlimit — löse ihn so oft du willst.
Dies ist ein kostenloses Multiple-Choice-Quiz mit 16 Fragen. Nach jeder Antwort siehst du, ob sie richtig war — immer mit Erklärung. Keine Anmeldung, kein Zeitlimit: Mach es so oft du willst und nutze den Lösungsschlüssel oben zum Wiederholen, vorher oder nachher.
Richtige Antwort: BNamespaces
Linux namespaces (PID, mount, network, IPC, UTS, user) isolate what a process can see, while cgroups limit how many resources (CPU, memory, I/O) it can consume.
Richtige Antwort: Bcgroups v2 provides a unified hierarchy, resolving resource controller conflicts and supporting rootless containers cleanly
cgroups v2 unifies resource management under a single hierarchy, eliminating cross-controller deadlocks, improving memory-pressure metrics, and supporting rootless cgroups.
Richtige Antwort: BIt defines a gRPC interface allowing the kubelet to interact with different container runtimes (like containerd or CRI-O)
The CRI is a gRPC specification enabling the kubelet to manage container lifecycles against various container runtimes (containerd, CRI-O) without modifying Kubernetes core code.
Richtige Antwort: Cetcd
etcd is a strongly consistent, distributed key-value store that acts as the single source of truth for all Kubernetes cluster state and specifications.
Richtige Antwort: BThe Linux Out-Of-Memory (OOM) killer terminates a process within the container (OOMKilled, exit code 137)
When memory usage breaches the cgroup limit, the Linux kernel triggers the OOM killer on that container, terminating the offending process and setting the Pod state to OOMKilled.
Richtige Antwort: AIt merges multiple read-only lower directories with a single read-write upper directory into a unified view
OverlayFS uses stacked read-only layers (lowerdir) from the container image and presents a single writable layer (upperdir) on top using copy-on-write mechanics.
Richtige Antwort: BMaintaining network rules on nodes (via iptables or IPVS) to route Service clusterIP traffic to backend Pods
kube-proxy watches the API server for Service and Endpoints objects and configures iptables, IPVS, or eBPF rules on the host to route service traffic to Pod IPs.
Richtige Antwort: BTo initialize and hold the shared network and IPC namespaces for all containers in the Pod
The Pause container starts first to set up the network, IPC, and UTS namespaces; all other containers in the Pod join these shared namespaces, allowing them to communicate over localhost.
Richtige Antwort: BIt inspects and potentially modifies an object payload before schema validation and storage in etcd
Mutating admission webhooks run before validating webhooks and etcd persistence, allowing admission controllers (like Istio sidecar injectors) to mutate resource definitions dynamically.
Richtige Antwort: BIt provides binary plugins called by the runtime to allocate IP addresses and wire network interfaces into Pod namespaces
When a Pod sandbox is created, the container runtime invokes the configured CNI plugin (e.g., Calico, Cilium) to set up virtual Ethernet interfaces, configure routing, and assign an IP.
Richtige Antwort: BNodePort exposes a high static port on every cluster node; Ingress acts as an intelligent Layer 7 reverse proxy routing to Services
NodePort exposes a Service across a dedicated high-range port (30000-32767) on all node IPs (Layer 4), whereas an Ingress controller provides Layer 7 reverse-proxying, SSL termination, and path routing.
Richtige Antwort: BThe minimum number or percentage of Pod replicas that must remain available during voluntary disruptions (like node drains)
A PDB limits the number of concurrently disrupted Pods during planned cluster administrative maintenance (like node upgrades and kubectl drain), preventing accidental application downtime.
Richtige Antwort: BExtended Berkeley Packet Filter (eBPF)
Cilium leverages eBPF inside the Linux kernel to attach programs directly to network sockets and interfaces, routing packets efficiently without traversing complex iptables rule chains.
Richtige Antwort: ATaints repel Pods from nodes unless the Pod possesses a matching toleration; affinities attract Pods to nodes
Taints are applied to nodes to repel Pods that do not explicitly tolerate the taint, whereas Node Affinity rules attract Pods to nodes matching specified label conditions.
Richtige Antwort: BExisting Pods continue executing normally, but newly created Pods remain in a 'Pending' state
The scheduler is only involved in assigning unbound Pods to nodes; if it fails, existing running Pods continue unaffected, but newly requested Pods remain unscheduled in 'Pending'.
Richtige Antwort: BIt ensures that if an attacker escapes the container, they only have unprivileged user access on the host
Rootless containers map the container's root user (UID 0) to a non-privileged UID on the host via user namespaces, preventing container escape exploits from gaining full host root privileges.