West Chester, PA
For the two routers to work independently of each other, you would need two WAN connections. You can't have two WAN connections on a residential account. The ONT only supports ONE MOCA WAN connection. And no, you can't have one coax and one cat5 WAN connection either.
1) The instructions under "Configuring the Actiontec", do not touch the wireless. The wireless on the Actiontec should still work. However, if the Actiontec lost it's WAN connection, because the D-Link grabbed the WAN connection, any devices on the Actiontec (wired or wireless) would not be able to get to the internet.
2) You have to have a primary router to service the WAN connection from the ONT. It can be your Linksys (via the D-Link) or it can be the Actiontec. You must pick one. You can't have both providing a WAN connection.
3) I was assuming you wanted the Linksys as your primary router. In that case, you need to provide a connection from the Actiontec to the Linksys LAN. This can be either Linksys LAN to Actiontec WAN or Linksys LAN to Actiontec LAN. Since you want to use the Actiontec wireless, I recommend the LAN-to-LAN. A LAN-to-WAN configuration would isolate wireless devices on the Actiontec on a separate subnet and they would not be able to see devices on the Linksys.
4) You could use the second D-Link to provide the LAN-to-LAN connection from the Linksys to the Actiontec instead of cat5.
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