An engineer is implementing MPLS OAM to monitor traffic within the MPLS domain. Which action must the engineer perform to prevent packets from being forwarded beyond the service provider domain when the LSP is down?
An engineer is implementing MPLS OAM to monitor traffic within the MPLS domain. Which action must the engineer perform to prevent packets from being forwarded beyond the service provider domain when the LSP is down?
To prevent MPLS OAM packets from being forwarded beyond the service provider domain when the LSP is down, the engineer should implement the destination address for the LSP echo request packet in the 127.x.y.z/8 network. This prevents the IP packet from being routed outside the service provider network because the 127.x.y.z/8 address range is reserved for loopback addresses and is not routable beyond the local device.
Actually the engineer needs to do nothing to prevent this because if not mentioned the destionation address is from 127./8 range, so it is prevented by default. A is not right because: Router#ping mpls ipv4 2.2.2.2/32 destination 10.0.0.1 % Destination address must be a 127.x.y.z address 10.0.0.1 is an invalid address Router#
D is correct see below: "The source address of the LSP echo request is the IP address of the LDP router generating the LSP request. The destination IP address is a 127.x.y.z/8 address, which prevents the IP packet from being switched to its destination if the LSP is broken. The 127.0.0.x destination address range prevents the OAM packets from exiting the egress provider-edge router, which keeps them from leaking from the service-provider network to the customer network." https://www.cisco.com/c/en/us/td/docs/wireless/asr_901s/scg/b_scg_for_asr901s/b_scg_for_asr901s_chapter_010001.pdf
D is correct
The source address of the LSP echo request is the IP address of the LDP router generating the LSP request. The destination IP address is a 127.x.y.z/8 address, which prevents the IP packet from being switched to its destination if the LSP is broken. The 127.0.0.x destination address range prevents the OAM packets from exiting the egress provider-edge router, which keeps them from leaking from the service-provider network to the customer network. https://www.cisco.com/c/en/us/td/docs/wireless/asr_901s/scg/b_scg_for_asr901s/b_scg_for_asr901s_chapter_010001.pdf
D is correct https://www.cisco.com/c/en/us/td/docs/routers/asr9000/software/asr9k-r7-5/mpls/configuration/guide/b-mpls-cg-asr9000-75x/implementing-mpls-oam-74x.html