Free Practice Questions for Cisco 300-445 Exam

According to the Designing and Implementing Enterprise Network Assurance (300-445 ENNA) curriculum, DNS testing is a fundamental component of ensuring application availability and performance. The ThousandEyes platform provides two primary types of DNS tests: DNS Server and DNS Trace .

To satisfy the specific requirements of monitoring IPv6 records and name server resolution times , the engineer must utilize the DNS Server test . This test type is designed to measure the performance of specific DNS servers by querying them for particular resource records.

Monitoring IPv6 Records: In the DNS system, IPv6 address records are known as AAAA records . Therefore, to monitor the availability and resolution of IPv6 addresses for a domain, the engineer must create a DNS Server test and set the query type to AAAA (Option B).

Monitoring Name Server Resolution Times: To measure how long it takes for a DNS server to return the authoritative name servers for a domain, the engineer must query for NS (Name Server) records . By creating a DNS Server test targeting the NS record (Option D), the platform can provide granular metrics on the response time and availability of those specific records from the perspective of the selected agents.

DNS Trace tests (Options C and E) are less suitable for measuring specific resolution times of a single server; instead, they are used to visualize the entire delegation path from the root servers down to the authoritative servers to identify where a " break " in the chain occurs. Furthermore, an A record query (Option A) only provides the IPv4 address, failing the requirement to monitor IPv6. By selecting DNS Server tests for AAAA and NS records, the administrator ensures they have the precise performance data needed to baseline and troubleshoot the organization ' s DNS health.

The Designing and Implementing Enterprise Network Assurance (300-445 ENNA) curriculum identifies Real User Tests (RUM) as the primary method for capturing actual browser-based interactions. While synthetic tests provide proactive baselines, Real user tests (Option C) provide visibility into the " lived experience " of an employee as they navigate corporate websites and SaaS platforms.

Real user tests utilize a lightweight browser extension (available for Chrome, Edge, and Safari) that is part of the Endpoint Agent deployment. When a user visits a domain defined in a " Monitored Domain Set, " the extension automatically begins recording performance metrics. This includes the time spent on each page, DNS resolution time, and a full browser waterfall of every object (images, scripts, CSS) loaded during the session. Crucially, it calculates an " Experience Score " for each session, allowing IT teams to identify if a user ' s frustration is caused by slow page rendering or underlying network issues.

In contrast:

Scheduled tests (Option A) and Dynamic tests (Option B) are forms of Synthetic Monitoring . They simulate traffic using a headless browser or simple network probes to check availability but do not record the actual clicks or browsing activity of the real human user.

Network Access tests (Option D) is not a standard test category in the ThousandEyes endpoint ecosystem; rather, network connectivity is a layer monitored within the other test types.

Therefore, Real user tests are the definitive tool for organizations needing to analyze actual employee browser behavior and the resulting application performance.

In the framework of Designing and Implementing Enterprise Network Assurance (300-445 ENNA) , selecting the appropriate agent for specific test types is a critical configuration step. The ThousandEyes platform utilizes different agent binaries and capabilities depending on the underlying hardware and software environment. Specifically, Page Load tests and Transaction tests require the agent to have a browser engine (Chromium) installed and functional to render web content and measure DOM-related metrics.

According to the ENNA implementation guidelines, not all Enterprise Agents support these browser-based tests. The exhibit displays a " New Test " configuration screen where the engineer is searching for " east1-agent-1 " . While other agents like " west-2-ag-1 " are visible, the designated agent is missing because it does not support Page load tests (Option D). This common occurrence happens when an Enterprise Agent is deployed on resource-constrained hardware—such as certain Cisco Catalyst 9000 switches or Cisco ISR 4000 series routers —where the Chromium browser package is either not supported or has not been enabled due to memory and CPU limitations.

When an agent lacks the required capabilities for a specific test layer (e.g., Web layer tests), it is automatically filtered out from the selection list in the ThousandEyes portal to prevent invalid test configurations. To identify compatible agents, an engineer can look for the " Browser " or " Dual Chromium " labels in the agent settings. If the " east1-agent-1 " were merely offline (Option A), disabled (Option B), or still registering (Option C), it would typically still appear in the list but with a status indicator showing its unavailability, rather than being entirely hidden from the test assignment menu. Therefore, the absence of the agent in a web-layer test configuration explicitly indicates a lack of functional support for the required browser-based metrics.