Examkin

Question

Difficulty: HardCisco DNA Center Enabled Device Management

A network engineer is deploying a factory-default Cisco Catalyst switch at a remote site where no local DHCP server or custom DHCP options exist. The switch serial number and Smart Account details have already been registered in the organization's Cisco Catalyst Center (Cisco DNA Center) portal. The switch is powered on and receives outbound internet connectivity. Which mechanism enables the switch to automatically discover its controller management IP address for zero-touch Day-0 Network Plug and Play (PnP) onboarding?

  1. The switch queries the Cisco PnP Connect cloud redirection service over HTTPS using its serial number and platform identity.Answer
  2. B
    The switch broadcasts Layer 2 CDP discovery frames across its uplink interfaces to receive controller IP credentials from neighbor switches.
  3. C
    The switch executes an embedded agent script using Ansible to pull configuration files directly from the controller REST API repository.
  4. D
    The switch sends an unencrypted HTTP POST message to its default gateway requesting an HTTP 302 redirect header containing the controller address.

Answer

The switch queries the Cisco PnP Connect cloud redirection service over HTTPS using its serial number and platform identity.
When a factory-default Cisco Catalyst switch boots up without receiving DHCP Option 43 or discovering a local DNS server entry for 'pnpserver', its built-in PnP agent contacts the Cisco Plug and Play Connect cloud service (devicehelper.cisco.com) via secure HTTPS. PnP Connect checks the switch's serial number against the customer's Smart Account and redirects the device to its registered Cisco Catalyst Center (Cisco DNA Center) management IP address.

Step-by-Step Solution

1
Identify the Day-0 Network Plug and Play (PnP) discovery order for unconfigured Cisco Catalyst switches.
The default PnP agent discovery sequence attempts DHCP Option 43 first, followed by local DNS lookup (pnpserver.domain), and finally Cisco PnP Connect cloud redirection.
Because DHCP server options and local DNS are absent in this scenario, the switch falls back to the internet-based cloud redirection service.
2
Analyze how Cisco PnP Connect functions for cloud redirection.
The switch initiates a secure HTTPS connection to Cisco's cloud portal (devicehelper.cisco.com) and presents its hardware serial number and PID.
Cisco Smart Software Manager matches the device serial number to the organization's Smart Account and returns the IP/FQDN of the assigned Cisco Catalyst Center instance.
3
Evaluate the alternative options against PnP architectural roles.
Layer 2 CDP, embedded Ansible agents, and HTTP POST gateway redirects are invalid PnP controller discovery mechanisms.
PnP is a controller-led, agent-initiated protocol specifically engineered for zero-touch provisioning over IP networks.

Key Concept

Cisco DNA Center / Catalyst Center Network Plug and Play (PnP) Day-0 Cloud Redirection
Rate this question

Topics

Cisco DNA Center Enabled Device Management

More questions from this topic