Which protocol is responsible for learning an IPv4 neighbor's MAC address?
The Address Resolution Protocol (ARP) is responsible for mapping an IPv4 address to a machine's MAC address. ARP operates at Layer 2 of the OSI model and is used to find the MAC address of a host given its IPv4 address. When a device wants to communicate with another device on the same local network, it uses ARP to discover the recipient's MAC address.
Juniper official documentation: ARP.
Networking standards: RFC 826.
Which statement is correct concerning exception traffic processing?
Exception traffic refers to packets that the Packet Forwarding Engine (PFE) cannot process normally and must be forwarded to the Routing Engine (RE) for further processing. This includes packets destined for the router itself or packets needing special handling that the PFE cannot provide. To protect the RE from being overwhelmed by such traffic, which could potentially impact the router's control plane functions, exception traffic is rate-limited. This means that there's a threshold to how much exception traffic can be sent to the RE, ensuring that the router's critical management and control functions remain stable and responsive even during high traffic volumes or attacks.
You have completed the initial configuration of your new Junos device. You want to be able to load this configuration at a later time.
Which action enables you to perform this task?
In Junos OS, the request system configuration rescue save command is used to save the current active configuration as a rescue configuration. This feature is particularly useful for preserving a known good configuration state that can be quickly reverted to in case of configuration errors or issues. By saving a rescue configuration, administrators can ensure that they have a reliable fallback option that can be loaded in the future to restore the device's operation without having to reconfigure from scratch. This is an essential practice for maintaining network stability and quick recovery.
Which two statements describe the result when you enter? at the command-line prompt? (Choose two.)
When you enter ? at the command-line prompt in Junos OS, the system provides assistance in two significant ways. Firstly, it lists the available commands and options that can be used at the current point in the command hierarchy, aiding users in understanding what commands they can execute next. Secondly, it displays summary information about those commands and options, providing brief descriptions or additional context that can help users understand the function of each command or option. This feature is particularly useful for learning the command structure or for quick reference when specific command syntax is forgotten.
Exhibit
user@router> show route 192.168.100.2
inet.O: 15 destinations, 17 routes (15 active, 0 holddown, 0 hidden) Limit/Threshold: 1048576/1048576 destinations
+ = Active Route, - = Last Active, * = Both 192.168.100.2/32 *[OSPF/IO] 00:14:29, metric 1
> to 172.16.1.6 via ge-0/0/1.0 [BGP/170] 00:06:49, localpref 100
AS path: 65102 I, validation-state: unverified > to 172.16.1.6 via ge-0/0/1.0
Referring to the exhibit, which statement is correct?
Referring to the exhibit, the presence of the '+' symbol next to the OSPF route for 192.168.100.2/32 indicates that this is the active route being used to forward traffic. The BGP route, although present, does not have the '+' symbol, indicating it is not the active route. In Junos OS, the routing table displays the active route with a '+' symbol, and the fact that the OSPF route has this symbol means it is the preferred path based on the routing protocol's decision process, which takes into account factors such as route preference (administrative distance) and metrics.
