Exam 350-501 topic 1 question 225 discussion

i tested it. It is the password blocking because of mistmatch. my answer is A

Answer: A Cisco is causing proble with cisco password, captial and small letter C

B is correct since the password has been set on the given exhibit already

Voting A B- There is no comment about statically set the router-id to lo0, by default LPD will chose the highest IP from a loopback interface unless the Loopback is shut or the router-id is configured C - Session protection is not need it D - timers can be different

A I think is the most likely but probably need both A and B. A. "You must configure authentication on both LDP peers using the same password; otherwise, the peer session is not established." B. the router-id is not manually configured (from what we see) so will by default use the highest IP on any loopback. No idea if that is L0 or another, it does not tell us C. session protection is not needed on R1, it ask for R2 and it is configured there already D. discovery hello times can be as set, not necessary to match the other end We see debug output possibly from "debug mpls ldp session state-machine" showing the ldp peer IP 10.0.0.1, not clear which router that is from but the loopbacks are 10.10.10.1 and 10.10.10.2 so the message is from the link and not the loopback.

log showing R2 received hello message from 10.0.0.1 and opening session with it So R1 is not using loopback0 as router id ---- Option B required to fulfill the objective ... Whether R2 bydefault using loopback0 as router id or not ... it is not clear. If it is using the interface IP, neighborship should be up without password ... When both the routers are forced to use loopback 0 as router id, password missmatch will come into picture so Option A is also required .... Further more Both routers are directy connected, defining static neighbor will not trigerred targetted LDP as it will rely more on discovery, so session protection will not work if one end is configured for session protection and other end not.R2 already enabled session protection so Option C si also required. .... OPTION A,B,C all are required what cisco valued most it is in hand of GOD. :)

just know that cisco doesn't show you the answer that easy in the question so i think is B

The passwords clearly look different in the question and if so, this would cause the LDP neighbor adj to fail. Although good practice, I'm not sure why configuring LDP router-id would cause this to establish by itself.