A Global IT organization has deployed Hybrid Connectivity for its intranet application. They have set up AWS Direct Connect from regional offices to AWS. Finance Servers are deployed in each region. Central HRservers are deployed in the us-west-1 region along with servers in each regional office. Finance servers need to be assessed locally while HR servers need to assess from all regions globally. IT Head wants to ensure that Finance server IP prefixes are advertised only in the region where it is deployed, while all servers globally should have connectivity to central HR servers in the us-west-1 region to upload employee attendance details. You are working as a Network engineer for this organization & have been assigned the task to completeBGP configuration for this setup. While advertising prefixes to BGP peer which tags can be used to control these prefixes advertisements?

Answer options:

A.Use BGP Community Tags 7224:9100 for the server to be accessed in each AWS region& no BGP community tags for servers to be accessed from all regions.
B.Use no BGP community tags for the server to be accessed in each AWS region& BGP Community Tags 7224:9300 for servers to be accessed from all regions.
C.Use BGP Community Tags 7224:9300 for the server to be accessed in each AWS region & BGP Community Tags 7224:9200 for servers to be accessed from all regions.
D.Use BGP Community Tags 7224:9200 for servers to be accessed in each AWS region & BGP Community Tags 7224:9300 for servers to be accessed from all regions.

Correct Answer – A
BGP Community tags can be used to control the advertisement of IP prefixes towards the Amazon network. With no BGP Community or Tag 7224:9300, prefixes will be advertised to all AWS regions, while with Tag 7224:9200, it will be advertised to AWS regions in that Continent. With BGP Community Tag 7224:9100, it will be advertised only to specific AWS regions in which it is part of & not to any other regions.In the above case, the client wants HR server IP prefixes to be only advertised in each region so they can be tagged with Community Tags 7224:9100. Finance servers need to be globally accessed so they can be advertised without any Tag.
Option B is incorrect as with no BGP community Tags which is a default option will advertise prefixes to all AWS regions.
Option C is incorrect as with Community Tag 7224:9300, the server IP Pool will be advertised to all regions.
Option D is incorrect as this will advertise server IP pool to all AWS regions in North America.
For more information on using BGP Community Tags for Prefix Advertisements, refer to the following URL
https://docs.aws.amazon.com/directconnect/latest/UserGuide/routing-and-bgp.html