Section 5.3 Demonstrate your acquired knowledge about if given a scenario, troubleshoot common issues with network services. This will demonstrate your proficiency for section 5.3 of the Network+ 10-009 objectives. 1 / 25 What is the key function of a default gateway on a client device? Resolves domain names Assigns VLANs Forwards packets destined for non-local subnets Controls switch port speed 2 / 25 A switch has ports in different VLANs, but routing between VLANs is not working. What is missing? ACL rules DNS entries Layer 3 interface MAC filtering 3 / 25 What routing issue occurs if no default route exists and a destination is not listed in the routing table? Packet is dropped DNS provides a fallback STP attempts reroute ICMP loop is created 4 / 25 What is the likely result of incorrect VLAN trunking between switches? Hosts are isolated and cannot reach other VLANs DHCP starvation Duplicate MAC flooding DNS cache poisoning 5 / 25 If a host is configured with the wrong IP address for its subnet, what is the effect? MAC address conflict Inability to communicate with hosts in the subnet VLAN ID reassigns automatically DNS request loops 6 / 25 A misconfigured ACL is blocking all outbound traffic. What’s the most likely reason? No NAT is configured There is no explicit "permit" rule before the implicit "deny all" Subnet mask mismatch Root bridge is offline 7 / 25 Which STP port state allows learning MAC addresses but not forwarding frames? Learning Listening Blocking Forwarding 8 / 25 A client cannot access any websites but can ping the gateway. What should be checked next? VLAN ID Subnet mask DNS configuration Port speed 9 / 25 A router’s default route points to an invalid next hop. What happens to unmatched traffic? It's redirected DNS forwards it It's dropped It's looped through STP 10 / 25 What is the impact of an incorrect subnet mask on a host? Broadcasts are disabled Host cannot properly determine its local network range STP is disabled DHCP requests fail 11 / 25 What port role in STP actively forwards traffic? Blocking Designated Listening Disabled 12 / 25 You see APIPA addresses (169.254.x.x) on several workstations. What is the cause? DHCP address pool exhausted or unreachable Incorrect VLAN assignment Bad DNS suffix Trunk misconfigured 13 / 25 What ACL misconfiguration can result in blocked HTTP access but allow ping? Allow all TCP ICMP allowed but TCP port 80 denied UDP port 53 allowed VLANs blocked 14 / 25 A user is placed in the wrong VLAN. What behavior is most likely? They receive duplicate IPs They can't access expected network resources DNS fails to resolve They loop back to the root bridge 15 / 25 If multiple routes exist to the same destination, how does a router choose the best one? Based on DNS TTL Based on administrative distance and metric Based on broadcast rate Based on MAC address 16 / 25 You observe that a switch port is continuously flapping between states. What could be a cause? DNS misconfiguration Network loop or physical layer issue Incorrect subnet mask ACL block 17 / 25 What is a primary role of the STP root bridge? To issue IP addresses To act as the central reference point for STP calculations To encrypt VLAN traffic To manage DNS requests 18 / 25 A PC has an IP of 192.168.1.10/255.255.255.0 but can't reach 192.168.2.1. What is likely wrong? Incorrect MAC address VLAN assignment is too high Subnet mask is preventing routing Port is in blocking state 19 / 25 What happens when two hosts are configured with the same static IP address? One host switches to DHCP STP disables the link Network conflict causes intermittent connectivity Both hosts connect with reduced bandwidth 20 / 25 Which situation indicates address pool exhaustion on a DHCP server? IP address conflicts across the network Clients receiving loopback addresses Clients fail to obtain IP addresses and default to APIPA DNS resolution errors 21 / 25 A routing table is missing a route to a remote network. What is a short-term solution? Reboot the router Increase TTL value Add a static route Disable STP 22 / 25 A host cannot communicate outside its subnet, but internal communication works. What is the likely issue? VLAN mismatch Incorrect default gateway Incorrect DNS server STP misconfiguration 23 / 25 A port is in a "blocking" STP state. What is the purpose of this state? To prevent loops by not forwarding traffic To increase trunk throughput To assign port VLANs To monitor port bandwidth 24 / 25 Which STP feature determines which switch will serve as the root bridge? PortFast configuration Bridge ID VLAN ID Trunk negotiation 25 / 25 What issue can occur if Spanning Tree Protocol (STP) is not enabled on a redundant switch network? VLAN mismatch Broadcast storm due to network loop Port security lockout Trunk misconfiguration Your score is 0% Restart quiz Return to CompTia N+ 10-009 Objectives
