D329 Networks and Security Applications - Set 4 - Part 2

Correct Answer: Duplicate components that take over when a primary fails

Redundancy provides backup components such as additional links, power supplies, or devices that assume the load when a primary element fails.

Correct Answer: Preventing switching loops in networks with redundant paths

Redundant switch links can create loops that flood the network. STP blocks redundant paths logically while keeping them available if the active path fails.

Correct Answer: Excessive broadcast traffic consuming network capacity, often from a loop

A broadcast storm occurs when broadcasts circulate endlessly, typically due to a switching loop, saturating links and rendering the network unusable.

Correct Answer: Combining multiple physical links into one logical higher-capacity link

Link aggregation bundles several physical connections into a single logical link, increasing bandwidth and providing redundancy if one member fails.

Correct Answer: The topology, devices, and connections in the environment

Network diagrams record physical and logical topology, device roles, addressing, and connections, which is essential for troubleshooting and change planning.

Correct Answer: Identify the problem and gather information

Structured troubleshooting begins by clearly identifying the problem and gathering information about symptoms, scope, and recent changes before theorizing causes.

Correct Answer: Most new problems are caused by a recent change

Environments that were working typically break because something changed, so identifying recent changes rapidly narrows the likely cause.

Correct Answer: Basic reachability and round-trip time to a host

Ping sends ICMP echo requests to test whether a host is reachable and measures round-trip latency, though some hosts block ICMP.

Correct Answer: The local host's IP configuration

These commands show the local interface configuration including IP address, subnet mask, and default gateway, often the first check when connectivity fails.

Correct Answer: Active network connections and listening ports on the local system

Netstat lists active connections, listening ports, and related statistics, useful for identifying unexpected services or suspicious outbound connections.

Correct Answer: Querying DNS to resolve names and inspect records

These tools query DNS servers directly, allowing administrators to verify records and diagnose name resolution problems independently of applications.

Correct Answer: DNS resolution is failing

Successful IP connectivity with failed name resolution isolates the problem to DNS configuration or the DNS server itself, since underlying routing works.

Correct Answer: Capturing and inspecting network traffic in detail

A packet analyzer captures frames and decodes protocol details, allowing precise diagnosis of communication problems and analysis of suspicious traffic.

Correct Answer: Captures may contain sensitive data and require authorization and protection

Packet captures can contain credentials and confidential data, so their use requires authorization and the resulting files must be stored and handled securely.

Correct Answer: Deliberately limiting throughput for certain traffic or users

Throttling caps the rate available to specific traffic, managing congestion and preserving capacity for higher-priority applications.

Correct Answer: Performance degradation, outages, and anomalous behavior

Monitoring continuously measures availability, performance, and traffic patterns, alerting administrators to problems and anomalies before users are affected.

Correct Answer: A record of normal performance used for comparison later

A performance baseline captures normal behavior so deviations can be recognized, distinguishing genuine anomalies from typical variation.

Correct Answer: Collecting management and status information from network devices

The Simple Network Management Protocol gathers status and performance data from devices and can generate traps alerting management systems to events.

Correct Answer: It provides authentication and encryption that earlier versions lack

SNMPv1 and v2c send community strings in cleartext with no encryption. SNMPv3 adds authentication and privacy, protecting management traffic.

Correct Answer: Administering devices through a separate dedicated management path

Out-of-band management uses a separate network or console path, allowing administration even when the production network is degraded or compromised.