ENARSI 1.6 to 1.8 PBR, VRF-Lite and BFD¶
These three objectives are about controlling and protecting forwarding. They are not about choosing routes. PBR overrides the destination lookup for selected traffic. VRF-Lite splits one router into several separate routing tables. BFD tells the routing protocols within milliseconds that a neighbour has gone. Two objectives are configure and verify, and ENARSI is a troubleshooting exam. Expect exhibits with show route-map, show vrf, show ip route vrf and show bfd neighbors output where you must spot why traffic takes the wrong path, leaks between VRFs or fails over slowly. BFD is describe, so its questions focus on concepts: modes, timers, detection time and client protocols.
| Objective | Verb | Page |
|---|---|---|
| 1.6 Policy-based routing: route-map match/set, next-hop verify-availability, local PBR, troubleshooting | Configure and verify | Policy-Based Routing |
| 1.7 VRF-Lite: VRF definitions, interfaces, per-VRF routing protocols, route leaking basics, troubleshooting | Configure and verify | VRF-Lite |
| 1.8 Bidirectional Forwarding Detection: asynchronous and echo modes, timers, client protocols | Describe | BFD |
Time budget: week 15 of the study plan, shared with 1.5 summarization. Allow about two days for PBR, two days for VRF-Lite and one day for BFD. Every page ends with a break/fix lab. Build the baseline, save it, then work through the faults one at a time.
Related practice¶
- Diagrams: N06 PBR next-hop decision, N07 VRF-Lite multi-tenant edge, N08 BFD with OSPF and BGP
- Simulation: Sim 08: PBR, VRF-Lite and BFD, a 30-minute troubleshooting ticket with one fault in each topic. Do it after the three labs on these pages.
- Question bank: ENARSI bank 1, questions 15 to 19
- Lab platform and addressing: Lab Setup
When you finish, take the PBR, VRF-Lite and BFD practice questions. Aim for 80% or better before moving on to 1.9 EIGRP.
Unlock the full question banks and cram sheets
A free account opens every question bank, the timed practice exams, the printable cram sheets, all the simulations and the lab files. Without one you see a 5-question sample of each.
No card needed. Study tips by email are optional and off unless you tick the box. Your address is never sold or shared. Privacy policy ยท Terms
Signed in as . Your account
You're on the free account, so lessons after the first module, question banks, exams and cram sheets show a sample. See Track Pass and All-Access
Also from NetManager Systems: NetManager, network monitoring for multi-vendor networks. Try the NetManager, NetDiag, PCAP Analyzer and OpsDash demos: every new account gets a free 7-day read-only login to each.