Recap - Connect the Floors

Two office floors. Host a1 (172.16.1.11/24) sits on switch swa; host b1 (172.16.2.11/24) on switch swb. Router core is cabled to swa (eth0) and swb (eth1) but has no addresses. Address the router with the .1 of each floor, give both hosts their gateway, and ping b1 from a1.

Expected output:

core eth0: 172.16.1.1/24 (mask 255.255.255.0, network 172.16.1.0/24)
core eth1: 172.16.2.1/24 (mask 255.255.255.0, network 172.16.2.0/24)
a1: gateway 172.16.1.1
b1: gateway 172.16.2.1
a1 -> b1: reply from 172.16.2.11 (ttl=63, via core)