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Policy Based Routing

July 25th, 2019 in ROUTE 300-101 Go to comments

Question 1

Explanation

Normal policy based routing (PBR) is used to route packets that pass through the device. Packets that are generated by the router (itself) are not normally policy-routed. To control these packets, local PBR should be used. For example: Router(config)# ip local policy route-map map-tag (compared with normal PBR: Router(config-if)# ip policy route-map map-tag)

Reference: http://www.cisco.com/c/en/us/td/docs/ios/12_2/qos/configuration/guide/fqos_c/qcfpbr.html

Question 2

Explanation

The set command specifies the action(s) to take on the packets that match the criteria. You can specify any or all of the following:

* precedence: Sets precedence value in the IP header. You can specify either the precedence number or name.
* df: Sets the “Don’t Fragment” (DF) bit in the ip header.
* vrf: Sets the VPN Routing and Forwarding (VRF) instance.
* next-hop: Sets next hop to which to route the packet.
* next-hop recursive: Sets next hop to which to route the packet if the hop is to a router which is not adjacent.
* interface: Sets output interface for the packet.
* default next-hop: Sets next hop to which to route the packet if there is no explicit route for this destination.
* default interface: Sets output interface for the packet if there is no explicit route for this destination.

route_map_set_command1.jpg

route_map_set_command.jpg

(Reference: http://www.cisco.com/en/US/docs/ios/12_2/qos/configuration/guide/qcfpbr_ps1835_TSD_Products_Configuration_Guide_Chapter.html)

Question 3

Explanation

The “show route-map “route-map name” displays the policy routing match counts so we can learn if PBR reacts to packets sourced from 172.16.0.0/16 or not.

show_route-map_divert.jpg

Question 4

Explanation

First we should check the access-list log, if the hit count does not increase then no packets are matched the access-list -> the policy based routing match counts will not increase.

Comments
  1. Lj
    September 22nd, 2017

    Passed today,
    this website is awesome, study the labs from here and the dumps from h*t*t*p*s*:*/*/*ww**w.*i*t*li**b*r*a*r*i*e*s*.*c*o*m*/(remove *)and it’s super easy

  2. Anonymous
    September 29th, 2017

    LJ,does it libraries have legit dumps?

  3. bluephoenix
    April 6th, 2018

    Lj

    are there sites offering free dumps?

  4. IQ
    June 15th, 2018

    No they are not.

  5. bodo1111
    July 24th, 2019

    Passed today with 840. New question about PBR.
    Which command isn’t available by default when the PBR is fast-switched? A. Set ip default B. Set ip interface C. Match clause with Named ACL D. Match clause with prefix-list. Answer is A

  6. GT 112223
    September 2nd, 2019

    Hi bodo1111, can you share the dumps you used?

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