What happens if the packet shown in the exhibit is received by a device running Junos OS?
What happens if the packet shown in the exhibit is received by a device running Junos OS?
When a device running Junos OS receives a packet, it is first processed by the Packet Forwarding Engine (PFE). The PFE analyzes the packet header to determine the appropriate action. In the case of packets with IP options, such as Record Route, they are not handled by the PFE alone. Instead, these packets require the involvement of the Routing Engine (RE) because the PFE is designed not to handle IP options. Therefore, the packet is received by the PFE first and then redirected to the RE for further processing.
IP options are exception traffic Packets addressed to the chassis, such as routing protocol updates, Telnet sessions, pings, traceroutes, and replies to traffic sourced from the RE; • IP packets with the IP options field (options in the packet’s IP header are rarely seen, but the PFE was purposely designed not to handle IP options; packets with IP options must be sent to the RE for processing); and • Traffic that requires the generation of Internet Control Message Protocol (ICMP) messages.
B. The packet is received by the PFE first and then redirected to the RE. Explanation: When a device running Junos OS receives a packet, it is first processed by the Packet Forwarding Engine (PFE). The PFE analyzes the packet header to determine the appropriate action, such as forwarding the packet to its destination or directing it to the Routing Engine (RE). In this case, the packet contains an Internet Control Message Protocol (ICMP) request, which is typically used for diagnostic purposes (e.g., ping requests). Because ICMP requests require control plane processing, the PFE would redirect the packet to the RE for further handling.
agreed B
agreed B
sure B
yes, it´s B
C- please look at destination MAC address is VMWARE not Juniper --> not exception traffic
I don't think this is relevant, also there are VMware-native vSRX and vMX images (not QEMU based).
In Junos OS, when an ICMP packet with the Record Route option is received, the routing engine (RE) is responsible for processing the packet. The Record Route option requires the RE's involvement to maintain and update the list of IP addresses as the packet traverses the network.