Free JN0-610 sample questions

Correct answer: The control interface IP assigned to the Control Node

The Contrail Control Node uses its control interface (often an IP on the management or a dedicated control network) to establish XMPP sessions with vRouters. While it can physically share a NIC with management, logically the XMPP connection targets the Control Node's IP defined in the configuration, distinct from the forwarding plane which handles encapsulated traffic.

Correct answer: Contrail creates a unique Virtual Network for each Kubernetes namespace and enables isolation by default.

When Contrail is integrated with Kubernetes, the default isolation mode maps every Kubernetes namespace to a distinct Contrail Virtual Network (VN). By default, these VNs are isolated from one another unless explicit policies or floating IPs are configured to allow traffic between them.

Correct answer: Define a Network Policy that references the Service Instance in its action and apply it to the source and destination VNs.

In Contrail, service chaining is policy-based. After defining the template and instance, you must create a Network Policy where the action is 'Apply Service' (pointing to your Service Instance). This policy must then be attached to the relevant Virtual Networks (Web and Database) to effect the routing change.

Correct answers: XMPP; Sandesh

XMPP is used for the control plane exchange of routing information and configuration data between the Control Node and the vRouter Agent. Sandesh is used for sending analytics data (logs, stats, flows) from the vRouter to the Analytics Collector.

Sandesh is the proprietary protocol used for analytics and telemetry streams from vRouter to the Analytics nodes.

Correct answer: False

This is False. The DPDK (Data Plane Development Kit) vRouter runs in **user space**, bypassing the Linux kernel networking stack to achieve higher throughput and lower latency. The Kernel vRouter (default/legacy) runs in kernel space.

Correct answer: The vRouter agent configuration file points to the wrong Control Node IP addresses or DNS names.

The vRouter agent initiates the XMPP connection to the Control Node. If the Control Node shows 0 peers, it means no agents have successfully connected. This is commonly caused by misconfiguration in the `contrail-vrouter-agent.conf` file where the Control Node list is incorrect, or a firewall is blocking port 5269 (XMPP).