Enterprise Network on GNS3 – Part 6 – Edge Router and ISPs
This is the sixth article from the series of the articles discussing the configuration of an entire enterprise network. The article explains the configuration of the edge router vIOS-EDGE-I and configuration of ISP routers. Now let's say few words about the router vIOS-EDGE-I. The router is Cisco IOSv Qemu appliance, version 15.6(2)T. It has assigned 512MB RAM by GNS3. The router connects all three parts of the company network to the Internet. These parts are the the campus network, data center and DMZ.
Picture 1 - Company Connection to the Internet via vIOS-EDGE-I
The company has assigned the prefix 195.1.1.0/24. Devices located in DMZ have assigned the prefix 195.1.1.128/25. The prefix 195.1.1.0/25 is assigned for devices hidden behind NAT. NAT is configured on vIOS-EDGE-I router, translating campus and data center subnets to the subnet 195.1.1.128/25. The router is connected to the upstream providers via their Ethernet ports Gi0/1 and Gi0/3. This is a single multi homed topology when a company is connected to two upstream providers with a single edge router. The entire prefix 195.1.1.0/24 is advertised to the both ISPs via BGP routing protocol. Continue reading