I have a network of 6 nodes connected via fiber. It is currently a layer2 network. The core switch is doing intervlan routing. To access the Internet, all sites have to go through the core before accessing the Internet via sw2 (see diagram). The STP root is at the core.
What I am trying to do is to figure out if I can slowly enable routed ports and enable EIGRP, two sites per day as they are far apart (~400 miles) from each other. It is quite risky to do it all remotely.
For the test, I enabled EIGRP between sw4 and sw5. I was able to ping the FW from sw4 and sw5. However, when I disabled fa0/2 on sw4, I lost the connection. It looks like there is only one way traffic (which is to go to the core and to the FW) and that will make my production network vulnerable to downtime. If the link between sw4 & core fails, users attached to sw4 cannot access the Internet or any servers attached to sw3.
Any thoughts? Thanks