Last Updated on July 31, 2021 by Admin 1
Refer to the following exhibit that shows four Cisco routers named rtr1, rtr2, rtr3, and rtr4:
The routers rtr2, rtr3, and rtr4 are eBGP peers of rtr1. In addition, rtr3 and rtr4 are also eBGP peers.
You want to implement the following requirements on rtr1:
The first attribute to select the best path is used.
Advertisements about 10.77.22.0/24 sent by rtr4 will be chosen over the advertisements sent by rtr3.
Which of the following commands should be included in the implementation plan for rtr1 to achieve the desired results? (Each option is a part of the solution. Choose all that apply.)
- neighbor 135.90.66.1 route-map set_weight out
- neighbor 135.90.66.6 route-map set_weight in
- route-map set_weight deny 10
- match ip-address 1
- set metric 100
- set weight 100
The following commands should be included in the implementation plan:
neighbor 135.90.66.6 route-map set_weight in
match ip-address 1
set weight 100
The neighbor 135.90.66.6 route-map set_weight in command specifies a route-map named set_weight for the incoming routing updates from 135.90.66.6 peer. The match ip-address 1 command specifies a criterion to match the IP address as specified in an access list. When the match criterion is met, the action specified in the set weight command is performed.
The set weight 100 command sets the weight attribute, which is a Cisco-defined attribute, to 100. The weight attribute is the first to be checked when BGP selects the best path between eBGP routers. This attribute is local to the router on which it is set and cannot be advertised to other routers.
The complete set of commands to achieve the desired results is as follows:
access-list 1 permit 10.77.22.0 0.0.0.255
router bgp 444
neighbor 135.90.66.3 remote-as 111
neighbor 135.90.66.1 remote-as 222
neighbor 135.90.66.6 remote-as 333
neighbor 135.90.66.6 route-map set_weight in
route-map set_weight permit 10
match ip-address 1
set weight 100
The set metric 100 command should not be included in the implementation plan to achieve the desired results. This command sets the metric to 100; however, the requirement is to use the first attribute to be checked, which is the weight attribute.
The neighbor 135.90.66.1 route-map set_weight out command should not be included in the implementation plan. This command forms an eBGP neighbor relationship with rtr3. The command also uses a route map named set_weight to set the weight attribute for the routes sent by rtr1. However, the weight attribute is local to rtr1 and cannot be set for outbound routes.
The route-map set_weight deny 10 command should not be specified in the implementation plan to achieve the desired results. This command creates a route map named set_weight. The deny keyword in this command indicates that if the match criterion is satisfied, then the set action is not performed. The permit keyword should be specified instead of the deny keyword to perform the set action when a match occurs.
Objective:
Layer 3 Technologies
Sub-Objective:
Identify suboptimal routing