View all questions & answers for the F5 BIG-IP LTM Specialist: Architect, Setup, and Deploy (301a) Exam Materials exam

F5 BIG-IP LTM Specialist: Architect, Setup, and Deploy (301a) Exam Materials - Question #117 Discussion

Comment Image Comment Image Comment Image

An LTM Specialist creates the virtual server for npath routing on port 80, but it fails to work as expected. The configuration is as follows: ltm virtual npath { destination 192.168.153.200:http mask 255.255.255.255 profiles { fastl4-1ooseclose { } } source 0.0.0.0/0 translate-address disabled translate-port disabled vs-index 3 } Which TMSH command should the LTM Specialist use to fix this issue? (Choose one answer)

  • A. modify ltm virtual npath profiles add { http }
  • B. modify ltm virtual npath source-port preserve-strict
  • C. modify ltm virtual npath source-address-translation { type automap }
  • D. modify ltm virtual npath auto-lasthop disabled
Correct Answer: B

Brave-Dump Community Votes

Answer: B (2 votes) 66.67%
Answer: D (1 vote) 33.33%

Community Explanations & Comments (3)

jansen 6 months ago
Selected: D
In nPath/DSR deployments, you must disable Auto Last Hop to prevent the BIG-IP from trying to manage the return path or interfering with the Layer 2 forwarding logic required for this mode.
Josko 1 month ago
Auto last hop is not used in nPATH routing. nPATH be L2 or L3 is design where initial traffic reaches F5, F5 has to loadbalance this traffic BUT there must be no SNAT and port must be strictly the same (either you uncheck port translation or you enable Preserver strict). This is because destination server has default gateway on router, firewall,... and return traffic will never be rerouted back to F5. Auto Last-Hop addresses another use case that handles asym. routing.
Anonymous User 4 months ago
Selected: B
https://my.f5.com/manage/s/article/K11116
Josko 1 month ago
Selected: B
B, destination server must receive original IP and original port of client that initiated connection