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100-490 RSTECH study materials
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100-490 RSTECH practice questions

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Question 1Routing and Switching Fundamentals

A switch receives a frame with destination MAC address ff:ff:ff:ff:ff:ff on a VLAN. How does the switch handle this frame?

  1. It floods the frame out all ports in that VLAN except the ingress port. Correct answer.
  2. It routes the frame to the default gateway for the VLAN.
  3. It forwards the frame only to the port learned for that MAC address.
  4. It drops the frame because broadcast addresses are not permitted on switched VLANs.

Explanation

A destination MAC of all ones is the Layer 2 broadcast address, and a switch floods broadcast frames to every port in the same broadcast domain except the one they arrived on. Flooding is also used for unknown unicast and multicast traffic. No MAC address table entry can exist for the broadcast address.

Question 2Routing and Switching Fundamentals

Which statement describes the purpose of the MAC address table on a Cisco switch?

  1. It records the spanning-tree topology changes for each VLAN.
  2. It stores IP-to-MAC bindings learned from ARP replies.
  3. It maps learned source MAC addresses to switch ports so frames can be forwarded selectively. Correct answer.
  4. It holds the routing table used to forward packets between VLANs.

Explanation

The switch builds its MAC address table by examining the source MAC of incoming frames and recording the ingress port. Later frames destined for a known MAC are forwarded only out the associated port. ARP and IP information are Layer 3 concerns handled elsewhere.

Question 3Routing and Switching Fundamentals

What is the default administrative distance of a static route on a Cisco router?

  1. 110
  2. 1 Correct answer.
  3. 90
  4. 120

Explanation

Cisco assigns a static route a default administrative distance of 1, making it highly preferred over dynamically learned routes. Administrative distance ranks the trustworthiness of route sources. Connected routes use distance 0 and are preferred over static routes.

Question 4Routing and Switching Fundamentals

Which address range is reserved for private use in IPv4?

  1. 172.0.0.0 through 172.255.255.255
  2. 169.254.0.0 through 169.254.255.255
  3. 172.16.0.0 through 172.31.255.255 Correct answer.
  4. 192.168.0.0 through 192.168.255.255 only

Explanation

RFC 1918 defines three private ranges: 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16. The 172.16.0.0/12 block spans 172.16.0.0 through 172.31.255.255. These addresses are not routable on the public Internet.

Question 5Routing and Switching Fundamentals

Which protocol prevents Layer 2 loops by placing redundant switch ports into a blocking state?

  1. Dynamic Host Configuration Protocol
  2. Link Aggregation Control Protocol
  3. Address Resolution Protocol
  4. Spanning Tree Protocol Correct answer.

Explanation

Spanning Tree Protocol elects a root bridge and computes a loop-free topology by blocking redundant ports. This prevents broadcast storms and frame duplication in a bridged network. The other protocols serve entirely different functions.

Question 6Routing and Switching Fundamentals

A router interface is configured with the address 192.168.10.1 255.255.255.0. Which command correctly enables the interface?

  1. interface up
  2. no shutdown Correct answer.
  3. ip routing
  4. shutdown

Explanation

Cisco router interfaces are administratively down by default, so the no shutdown command is required to bring an interface into service. Assigning an IP address alone does not enable it. The shutdown command does the opposite.

Question 7Routing and Switching Fundamentals

Which device forwards frames based on MAC addresses within a single broadcast domain?

  1. Hub
  2. Router
  3. Firewall
  4. Layer 2 switch Correct answer.

Explanation

A Layer 2 switch learns MAC addresses and forwards frames selectively within a broadcast domain. A hub simply repeats signals to all ports without any addressing logic. Routers and firewalls operate at Layer 3 and above.

Question 8Routing and Switching Fundamentals

What does the command ip route 0.0.0.0 0.0.0.0 203.0.113.1 configure?

  1. A summary route for the 203.0.113.0/24 network
  2. A floating static route with an administrative distance of 1
  3. A default route pointing to next hop 203.0.113.1 Correct answer.
  4. A host route for 203.0.113.1

Explanation

The prefix 0.0.0.0 with mask 0.0.0.0 matches every destination, so this command installs a default route. The next hop is the address 203.0.113.1. A default route is used when no more specific route matches.

Question 9Routing and Switching Fundamentals

A switch port is configured with the command switchport port-security. What must typically be true for port security to function on that interface?

  1. The port must be a routed port with no VLAN membership.
  2. The port must be an SVI with an IP address assigned.
  3. The port must be a member of a port channel.
  4. The port must be configured as an access port or have a supported trunk configuration. Correct answer.

Explanation

Port security restricts which source MAC addresses may send traffic on a switch port and requires the port to be in a Layer 2 switching mode, typically access. The feature is not applied to routed ports. Port channels and SVIs are not prerequisites.

Question 10Routing and Switching Fundamentals

Which OSPF packet type is used to discover neighbors and confirm bidirectional communication?

  1. Hello Correct answer.
  2. Link State Acknowledgment
  3. Link State Update
  4. Database Description

Explanation

OSPF routers send Hello packets on their interfaces to discover neighbors and to verify that two-way communication exists. Hello packets carry parameters such as the router ID, area ID, and hello/dead timers that must match. The other packet types synchronize databases and acknowledge updates.

Question 11Routing and Switching Fundamentals

A router has two routes to 10.1.1.0/24: an OSPF route with metric 20 and a static route with metric 1. Which route is installed in the routing table and why?

  1. The static route, because it has a lower administrative distance than OSPF. Correct answer.
  2. Both routes are installed and load-balanced equally.
  3. The OSPF route, because dynamic routes always override static routes.
  4. The OSPF route, because it has a lower metric than the static route.

Explanation

When multiple sources offer a route to the same prefix, the router first compares administrative distance, which measures the trustworthiness of the source. Static routes use distance 1 and OSPF uses 110, so the static route wins. Metrics are compared only among routes from the same protocol.

Question 12Routing and Switching Fundamentals

Which command displays the OSPF neighbor adjacencies and their current states on a Cisco router?

  1. show ip route ospf
  2. show ip protocols
  3. show ip ospf interface
  4. show ip ospf neighbor Correct answer.

Explanation

The show ip ospf neighbor command lists each neighbor, its router ID, and its adjacency state, such as FULL or 2WAY. This is the primary tool for verifying that adjacencies have formed correctly. The other commands show routes, protocol settings, or per-interface parameters.

Question 13Routing and Switching Fundamentals

What is the result of configuring switchport mode trunk on an interface?

  1. The interface is assigned to a single VLAN and strips all tags.
  2. The interface carries traffic for multiple VLANs using 802.1Q tagging. Correct answer.
  3. The interface disables VLAN tagging and forwards untagged frames only.
  4. The interface becomes a routed port with an IP address.

Explanation

A trunk port carries traffic for multiple VLANs and uses 802.1Q tags to identify the VLAN of each frame. Access ports, by contrast, belong to a single VLAN. Trunking is used to connect switches and to reach routers or servers that need multiple VLANs.

Question 14Routing and Switching Fundamentals

Which statement about the native VLAN on an 802.1Q trunk is correct?

  1. Frames on the native VLAN are always double-tagged.
  2. The native VLAN must be VLAN 1 and cannot be changed.
  3. Frames on the native VLAN are sent untagged across the trunk. Correct answer.
  4. The native VLAN is used only for management traffic.

Explanation

802.1Q inserts a tag into frames for all VLANs except the native VLAN, whose frames traverse the trunk untagged. Both ends of a trunk should agree on the native VLAN to avoid misforwarding. The native VLAN defaults to VLAN 1 but can be changed.

Question 15Routing and Switching Fundamentals

A host with address 192.168.1.50/24 needs to reach 192.168.2.20/24. What does the host do first?

  1. It drops the packet because the destination is outside its subnet.
  2. It sends an ARP request for 192.168.2.20 on its local segment.
  3. It sends the packet to its default gateway because the destination is on a different subnet. Correct answer.
  4. It sends the packet directly to 192.168.2.20 using its own MAC address.

Explanation

The host compares the destination address with its own subnet mask and determines that 192.168.2.20 lies on a different network. It therefore forwards the packet to its configured default gateway, which routes it onward. Direct ARP for a remote host would fail because that host is not on the local segment.

Question 16Routing and Switching Fundamentals

Which spanning-tree port state forwards user traffic and learns MAC addresses?

  1. Learning
  2. Listening
  3. Blocking
  4. Forwarding Correct answer.

Explanation

Only the forwarding state both relays user frames and populates the MAC address table. The learning state builds the MAC table but does not forward user traffic. Blocking and listening states do neither.

Question 17Routing and Switching Fundamentals

Which command assigns a switch port to VLAN 20 as an access port?

  1. switchport mode access 20
  2. switchport access vlan 20 Correct answer.
  3. switchport trunk native vlan 20
  4. vlan 20 access

Explanation

The interface-level command switchport access vlan 20 places the port into VLAN 20 for untagged access traffic. The port should also be set to access mode with switchport mode access. The other commands either configure trunking behavior or are invalid syntax.

Question 18Routing and Switching Fundamentals

A router receives a packet destined for 10.10.10.5. Its routing table contains 10.10.10.0/24 and 10.0.0.0/8. Which entry is used?

  1. 10.0.0.0/8, because it covers a larger address space.
  2. Both entries, because the router load-balances across matches.
  3. Neither entry, because the destination is a host address.
  4. 10.10.10.0/24, because it is the longest matching prefix. Correct answer.

Explanation

Cisco routers use longest prefix match, so the most specific route that contains the destination is selected. The /24 entry matches 10.10.10.5 and is more specific than the /8 entry. Load balancing applies only to equal-cost routes for the same prefix.

Question 19Routing and Switching Fundamentals

Which two features are provided by a first-hop redundancy protocol such as HSRP? (Choose the best answer.)

  1. Encryption of traffic between VLANs
  2. Dynamic IP address assignment for end hosts
  3. Layer 2 loop prevention across redundant switches
  4. A shared virtual IP and MAC address that hosts use as their gateway Correct answer.

Explanation

HSRP and similar protocols present a virtual IP and virtual MAC address shared by a group of routers, so hosts can use a stable default gateway. If the active router fails, a standby router takes over the virtual address. The protocol does not assign addresses, prevent Layer 2 loops, or encrypt traffic.

Question 20Routing and Switching Fundamentals

A network engineer wants to verify which VLANs are allowed on a trunk and which is the native VLAN. Which command provides this information?

  1. show interfaces trunk Correct answer.
  2. show vlan brief
  3. show mac address-table
  4. show spanning-tree summary

Explanation

The show interfaces trunk command lists trunk ports along with allowed VLANs, active VLANs, and the native VLAN. It is the standard verification tool for trunk configuration. The other commands report VLAN membership, STP summary data, or MAC learning.

Question 21Routing and Switching Fundamentals

A router interface is configured with the address 10.0.0.1/30. How many usable host addresses exist on that subnet?

  1. 6
  2. 2 Correct answer.
  3. 4
  4. 1

Explanation

A /30 prefix leaves 2 host bits, giving 4 total addresses. Subtracting the network and broadcast addresses leaves 2 usable host addresses. This is why /30 links are common on point-to-point router connections.

Question 22Routing and Switching Fundamentals

An engineer configures a static route with administrative distance 200 to serve as a backup for an OSPF-learned route. What is this configuration called?

  1. A directly connected route
  2. A summary route
  3. A default route
  4. A floating static route Correct answer.

Explanation

A floating static route uses an administrative distance higher than that of the primary dynamic route, so it is installed only if the dynamic route disappears. Setting distance 200 makes it less preferred than OSPF's 110. When OSPF fails, the static route becomes active.

Question 23Routing and Switching Fundamentals

Two OSPF routers are connected but remain stuck in the EXSTART state. Which condition most likely explains this?

  1. Different router priority values on the interfaces
  2. An MTU mismatch between the two interfaces Correct answer.
  3. Different OSPF process IDs on each router
  4. A mismatch in the hello timer values

Explanation

During EXSTART the routers exchange Database Description packets and negotiate a master/slave relationship, and a mismatched MTU can prevent this negotiation from completing. Hello or dead timer mismatches would prevent the adjacency from forming at all. Process IDs and priorities are locally significant and do not block this stage.

Question 24Routing and Switching Fundamentals

A switch has three ports in the same VLAN configured as access ports, and a frame arrives with an unknown destination MAC. How is the frame handled?

  1. It is dropped because the destination is unknown.
  2. It is sent back out the ingress port only.
  3. It is flooded out the other two access ports in that VLAN. Correct answer.
  4. It is forwarded to the router for resolution.

Explanation

When a switch has no MAC address table entry for the destination, it floods the frame within the VLAN to all other ports in that broadcast domain. This unknown unicast flooding allows the destination to respond and be learned. The ingress port is excluded from the flood.

Question 25Routing and Switching Fundamentals

A router needs a route to 172.16.0.0/16 that matches only that network and its subnets. Which configuration accomplishes this with a static route?

  1. ip route 172.16.0.0 255.255.0.0 192.0.2.1 250
  2. ip route 0.0.0.0 0.0.0.0 192.0.2.1
  3. ip route 172.16.0.0 255.255.0.0 192.0.2.1 Correct answer.
  4. ip route 172.16.0.0 255.255.255.0 192.0.2.1

Explanation

The prefix 172.16.0.0 with mask 255.255.0.0 is the /16 network, and the route matches that network and any more specific subnets within it. The next hop is 192.0.2.1. The other options either use the wrong mask or add an administrative distance.

Question 26Routing and Switching Fundamentals

Which characteristic identifies a Layer 2 switch rather than a Layer 3 router?

  1. It forwards packets using destination IP addresses between broadcast domains.
  2. It rewrites the source IP address of each packet it forwards.
  3. It decrements the TTL field of each frame before forwarding.
  4. It forwards frames using destination MAC addresses within one broadcast domain. Correct answer.

Explanation

A Layer 2 switch builds a MAC address table and forwards frames based on the destination MAC address, staying within a single broadcast domain. Routers move packets between broadcast domains using IP addresses and decrement TTL.

Question 27Routing and Switching Fundamentals

A host is configured with the address 172.16.5.10 255.255.255.192. Which address is the directed broadcast address of its subnet?

  1. 172.16.5.64
  2. 172.16.5.63 Correct answer.
  3. 172.16.5.127
  4. 172.16.5.255

Explanation

A /26 mask creates blocks of 64 addresses. The host 172.16.5.10 falls in the block 172.16.5.0 through 172.16.5.63, so the broadcast address is 172.16.5.63.

Question 28Routing and Switching Fundamentals

Which statement describes the purpose of the administrative distance value in a Cisco routing table?

  1. It ranks routes learned from different sources to the same destination. Correct answer.
  2. It limits the number of hops a packet may traverse.
  3. It measures the delay of a path in tens of microseconds.
  4. It sets the priority of a frame inside an 802.1Q tag.

Explanation

Administrative distance is a trustworthiness value used to compare routes from different sources for the same prefix; the lower value wins. Metric compares paths within a single routing protocol, and hop limits and CoS are unrelated functions.

Question 29Routing and Switching Fundamentals

Which command on a Cisco IOS router creates a static route to 192.168.50.0/24 through next hop 10.1.1.2?

  1. route add 192.168.50.0 mask 255.255.255.0 10.1.1.2
  2. ip route 192.168.50.0 255.255.255.0 10.1.1.2 Correct answer.
  3. ip route 10.1.1.2 255.255.255.255 192.168.50.0
  4. ip route 192.168.50.0 10.1.1.2 255.255.255.0

Explanation

The IOS syntax is ip route followed by the destination network, its subnet mask in dotted decimal, and then the next-hop address. The mask must come before the next hop.

Question 30Routing and Switching Fundamentals

Two switches are connected by a link that carries VLANs 10, 20, and 30. Which configuration on the link allows all three VLANs while tagging frames?

  1. switchport mode trunk Correct answer.
  2. switchport mode access
  3. switchport nonegotiate on an access port
  4. switchport mode dynamic auto with no negotiation

Explanation

A trunk port carries multiple VLANs and tags frames with 802.1Q headers so the far end can identify each VLAN. An access port belongs to a single VLAN and sends untagged frames.

Question 31Routing and Switching Fundamentals

What is the primary function of the Spanning Tree Protocol on a switched network?

  1. To prevent Layer 2 loops by blocking redundant paths Correct answer.
  2. To authenticate hosts before they may send frames
  3. To prevent Layer 3 loops by aging out routing entries
  4. To load-balance traffic across all redundant links simultaneously

Explanation

STP elects a root bridge and places redundant ports into a blocking state so that a single active path exists for each VLAN, preventing broadcast storms and MAC table instability. It does not balance traffic across all links at once.

Question 32Routing and Switching Fundamentals

An engineer needs the router to obtain an address for its WAN interface from the service provider. Which interface configuration accomplishes this?

  1. ip dhcp pool
  2. ip helper-address
  3. ip address dhcp Correct answer.
  4. ip address negotiated static

Explanation

The ip address dhcp interface command makes the router act as a DHCP client and lease an address from the upstream server. The ip dhcp pool command configures the router as a server, not a client.

Question 33Routing and Switching Fundamentals

Which address range is reserved for link-local IPv6 addresses?

  1. FC00::/7
  2. FF02::/16
  3. FE80::/10 Correct answer.
  4. 2001:DB8::/32

Explanation

IPv6 link-local addresses are formed from the FE80::/10 prefix and are used for neighbor discovery and next-hop communication on a single link. They are never routed.

Question 34Routing and Switching Fundamentals

A router interface is configured with the address 10.20.30.1 255.255.255.248. How many usable host addresses are available on that subnet?

  1. 6 Correct answer.
  2. 30
  3. 8
  4. 14

Explanation

A /29 mask leaves 3 host bits, giving 8 total addresses. Subtracting the network and broadcast addresses leaves 6 usable host addresses.

Question 35Routing and Switching Fundamentals

Which protocol provides default gateway redundancy by allowing multiple routers to share a virtual IP address?

  1. HSRP Correct answer.
  2. LACP
  3. LLDP
  4. STP

Explanation

HSRP lets two or more routers present a shared virtual IP and MAC address to hosts, with one active and one standby, so a host default gateway survives a router failure. The other protocols serve unrelated functions.

Question 36Routing and Switching Fundamentals

Which command displays the contents of a switch's MAC address table along with the associated VLANs?

  1. show arp
  2. show ip route
  3. show vlan brief
  4. show mac address-table Correct answer.

Explanation

The show mac address-table command lists learned MAC addresses, their ports, and their VLANs. The other commands display routing, ARP, or VLAN membership information instead.

Question 37Routing and Switching Fundamentals

A router has an interface with the address 192.168.1.1/24 and a host on that subnet sends a packet to 192.168.1.200. What does the router do with the packet?

  1. It sends the packet to its default gateway for further lookup.
  2. It forwards the packet out the directly connected interface after resolving the destination MAC. Correct answer.
  3. It drops the packet because no static route exists for the host.
  4. It rewrites the destination address to the interface address.

Explanation

A connected route for 192.168.1.0/24 is installed automatically when the interface is up. The router resolves the destination MAC with ARP and forwards the frame directly out that interface.

Question 38Routing and Switching Fundamentals

Which OSPF router role generates the router LSA (Type 1) for its own area?

  1. Every OSPF router Correct answer.
  2. Only the designated router
  3. Only the backup designated router
  4. Only the autonomous system boundary router

Explanation

Every OSPF router originates a Type 1 router LSA describing its own links and their states within an area. The DR, BDR, and ASBR roles affect flooding and external routing but not the basic generation of Type 1 LSAs.

Question 39Routing and Switching Fundamentals

Which statement about a switch port configured with the command switchport mode access is correct?

  1. It belongs to one VLAN and sends untagged frames to the attached device. Correct answer.
  2. It carries all VLANs and tags every frame with an 802.1Q header.
  3. It drops all frames until a native VLAN is configured.
  4. It negotiates trunking with the neighbor using DTP.

Explanation

An access port is a member of exactly one VLAN and presents untagged traffic to the end device. Tagging and DTP negotiation are characteristics of trunk-capable ports.

Question 40Routing and Switching Fundamentals

A network uses the address 10.0.0.0/8. Which subnet mask creates subnets that each support at least 500 hosts?

  1. 255.255.255.128
  2. 255.255.255.192
  3. 255.255.255.0
  4. 255.255.254.0 Correct answer.

Explanation

Supporting 500 hosts requires 9 host bits, since 2^9 minus 2 equals 510 usable addresses. A /23 mask, 255.255.254.0, leaves exactly 9 host bits.

Question 41Routing and Switching Fundamentals

Which mechanism allows a host on VLAN 10 to obtain an address from a DHCP server located on VLAN 20?

  1. An access list permitting UDP port 67
  2. A static route pointing to the DHCP server
  3. A trunk allowing only VLAN 20
  4. An ip helper-address configured on the VLAN 10 interface Correct answer.

Explanation

DHCP broadcasts do not cross routers, so the ip helper-address command on the client-facing interface forwards the request as unicast to the remote server. The reply returns through normal routing.

Question 42Routing and Switching Fundamentals

Which two pieces of information does a Cisco router use to make a forwarding decision for an inbound packet? (Choose the best answer.)

  1. The source MAC address and the ingress VLAN
  2. The destination MAC address and the ARP cache
  3. The destination IP address and the longest matching prefix in the routing table Correct answer.
  4. The source IP address and the administrative distance

Explanation

The router looks up the destination IP address and selects the most specific matching prefix, using administrative distance and metric only to break ties among equal prefixes. MAC addresses are resolved after the route is chosen.

Question 43Routing and Switching Fundamentals

Which statement correctly describes the difference between a collision domain and a broadcast domain?

  1. A router port and a switch port always belong to the same collision domain.
  2. Each switch port is its own collision domain, while all ports in one VLAN share a broadcast domain. Correct answer.
  3. Broadcast domains are limited to two devices, while collision domains are unlimited.
  4. Each VLAN is its own collision domain, while all switch ports share one broadcast domain.

Explanation

Full-duplex switch ports isolate collisions per port, so each port is a separate collision domain. Broadcasts flood to every port in the same VLAN, so a VLAN defines a broadcast domain.

Question 44Routing and Switching Fundamentals

An engineer wants a static route to be used only when the primary OSPF route to the same prefix is unavailable. Which configuration achieves this?

  1. A floating static route with an administrative distance greater than 110 Correct answer.
  2. A directly connected route to the same prefix
  3. A default route with next hop 0.0.0.0
  4. A static route with the default administrative distance of 1

Explanation

OSPF routes carry an administrative distance of 110, so a static route with a higher distance, such as 200, loses to OSPF while it is present and takes over when it disappears. This is the floating static route technique.

Question 45Routing and Switching Fundamentals

Which command verifies the configured IP address and operational status of a router interface?

  1. show ip route summary
  2. show running-config interface
  3. show controllers serial
  4. show ip interface brief Correct answer.

Explanation

show ip interface brief lists each interface with its IP address, status, and protocol state in a compact table. The running configuration shows intended settings but not live status.

Question 46Routing and Switching Fundamentals

Two routers connected over a point-to-point link both use the address 10.0.0.1/30. What is the most likely result?

  1. The link works because the routers negotiate unique addresses automatically.
  2. The link works because /30 provides four usable addresses.
  3. The link fails because /30 has no usable host addresses.
  4. The link fails because both ends claim the same address in a two-address subnet. Correct answer.

Explanation

A /30 provides exactly two usable addresses, and each end of a point-to-point link must use a different one. Duplicating 10.0.0.1 causes an address conflict and the adjacency cannot form correctly.

Question 47Routing and Switching Fundamentals

Which feature of a Layer 3 switch allows it to forward traffic between VLANs without a separate router?

  1. Switched virtual interfaces configured for each VLAN Correct answer.
  2. Access ports assigned to a management VLAN
  3. Port security with sticky MAC addresses
  4. EtherChannel bundles between access switches

Explanation

A Layer 3 switch uses switched virtual interfaces (SVIs) that act as routed gateways for each VLAN, allowing inter-VLAN forwarding in hardware. Access ports, EtherChannels, and port security are Layer 2 functions.

Question 48Routing and Switching Fundamentals

A router receives three routes to 10.1.1.0/24: OSPF with metric 20, EIGRP with metric 1000, and a static route with distance 1. Which route is installed in the routing table?

  1. All three routes are installed and load-balanced
  2. The OSPF route
  3. The static route Correct answer.
  4. The EIGRP route

Explanation

When multiple sources offer the same prefix, the router compares administrative distance first. The static route has distance 1, lower than EIGRP's 90 and OSPF's 110, so only it is installed.

Question 49Routing and Switching Fundamentals

What does configuring switchport port-security maximum 2 on an access port accomplish?

  1. It limits the port to two learned MAC addresses at a time. Correct answer.
  2. It allows two devices to share one MAC address.
  3. It sets the port speed to two megabits per second.
  4. It limits the port to two VLANs on a trunk.

Explanation

The maximum keyword sets how many secure MAC addresses the port may learn before a violation occurs. It is a Layer 2 security control and does not affect VLAN membership or speed.

Question 50Routing and Switching Fundamentals

Which statement about the OSPF designated router on a multi-access segment is correct?

  1. It prevents all other routers from receiving hello packets.
  2. It is elected only on point-to-point links.
  3. It forms full adjacencies with all routers and originates the network LSA. Correct answer.
  4. It replaces the need for an area border router.

Explanation

On a broadcast segment, the DR establishes full adjacencies with every other router and generates the Type 2 network LSA describing the segment. This reduces the number of adjacencies and LSA floods.