Juniper JN0-105 Practice Test - Questions Answers, Page 5

The show route table inet6.0 command displays all IPv6 routes in the default routing instance. In Junos OS, the routing table for IPv6 addresses is referred to as inet6.0, whereas inet.0 is used for IPv4 unicast routes. The other options do not correspond to the correct IPv6 routing table.

Juniper official documentation: Junos OS Routing Tables Overview.

In Juniper firewall filter configurations, 'discard' and 'accept' are two valid terminating actions for a term within a filter. The 'discard' action drops the packet, preventing it from reaching its intended destination, while the 'accept' action allows the packet to pass through the filter, proceeding to its next hop or destination. 'Count' is a non-terminating action that increments a counter every time a packet matches the term but does not inherently determine the packet's fate. 'Next term' directs the evaluation to proceed to the next term in the filter for further processing, also a non-terminating action.

Firewall filters in Junos OS are stateless, meaning they process each packet individually without regard to the state of a connection or sequence of packets. These filters can match various packet attributes, including those at Layer 4, such as TCP and UDP port numbers. This allows for granular control over traffic based on the type of service or application. Unlike stateless filters, stateful firewalls keep track of the state of active connections and make decisions based on the context of the traffic flow, which is not a capability of Junos firewall filters. Additionally, Junos firewall filters primarily operate up to Layer 4 and do not natively inspect Layer 7 parameters, which involve application-level data.

Issuing the rollback 0 command in Junos OS will discard any uncommitted changes and revert to the last committed configuration. This command effectively cancels any configuration changes that have been made but not yet committed, ensuring that the device returns to its previous stable state.

'rollback 0 ...................................(rolls back the changes just made )' from Useful Juniper Commands.txt.

Juniper official documentation: Rolling Back a Configuration.

The request system zeroize media command on a Junos device securely erases all data, including configuration and log files, and resets the device to its factory default settings. This command is used when redeploying a device to ensure no residual data remains from its previous deployment. It's a comprehensive and secure way to clear all configurations and data, making the device as if it were new. The other commands listed do not perform a full reset to factory defaults; for example, show system storage displays storage information, and request system storage cleanup offers to delete unnecessary files without resetting the device to factory settings.

In a Juniper Networks device, the Packet Forwarding Engine (PFE) processes unicast traffic by forwarding it according to the existing entries in the forwarding table. When the PFE encounters unicast traffic destined for an address that has a corresponding entry in the forwarding table, it directs the traffic through a specific outgoing interface or port toward its destination. This process is based on the most efficient path determined by the routing protocols in use, ensuring that the packet reaches its intended destination through a singular path, unless specific configurations such as load balancing are in place.

Transit traffic that traverses the forwarding plane of a Layer 3 router includes both unicast and multicast traffic types. Unicast traffic is directed from a single source to a single destination, while multicast traffic is sent from one source to multiple destinations that are part of a multicast group. These types of traffic are efficiently routed through the network by leveraging the router's forwarding plane capabilities. Exception traffic, which requires special handling by the control plane, and broadcast traffic, which is typically limited to a single broadcast domain and not usually forwarded by Layer 3 routers, are not considered standard types of transit traffic for the forwarding plane of a router.

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.

The load-balance per-flow statement in the Junos OS policy-options configuration enables flow-based load balancing in the forwarding table. This means that the traffic is distributed across multiple paths based on flows, where a flow is typically identified by attributes such as source and destination IP addresses, and possibly layer 4 information like TCP/UDP ports. This allows for more granular and efficient utilization of available paths, avoiding overloading a single path. The policy does not enable per-packet load balancing, which would send individual packets of the same flow over different paths, potentially causing out-of-order delivery issues. The policy's placement in the forwarding-table export suggests it's intended to influence forwarding behavior, not just routing protocol decisions, and does not necessarily have to be applied under the protocols hierarchy.