I have spent hours with technical support on this issue. I am quite surprised by their admission. There is a design flaw apparently with any Linksys router that has Linksys Smart Wifi. Static DNS settings are simply ignored.
The Smart Wifi settings will allow you go to Connectivity, then Local Network, and enable the DHCP server, which then allows you to manually enter static DNS settings. However, in reality, the router ignores them. The explanation given by JC with Belkin is "this is a "feature" of Linksys Smart Wifi which automatically points to the router to the cloud......." He finally admitted that this "feature" causes the router to ignore static DNS entered by the user.
So, I asked him to clarify my understanding that Linksys has a design flaw and basically is selling a EA6400 wireless router that doesn't (cannot) perform as advertised. He confirmed this. I explained that there were two solutions, (1) send me a router that does perform as advertised, or (2) refund my money. He said it was out of the ninety day warranty and, since I bought it from Sam's Club, and not directly from Linksys, that he could not refund my money. I did not accept his non-solution. He passed the issue to "upper management" and I am awaiting a proper solution.
I have had this router for about one year. When I first bought it, it did not work properly out of the box. Technical support had me update to the latest firmware and then change some settings. Then it worked well.
I have children and wanted an internet filter for porn, malware, phishing , etc. Our local school suggested OpenDNS. It is a free service that simply has you point your router to their filtered servers. This requires my changing the DNS settings as described above. Then any device on my home network will be filtered, because the router is pointing all internet traffic to OpenDNS. Well, it doesn't work with Linksys Smart Wifi. Technical support has verified firmware, had me reset it numerous times, verified all settings, only to then admit that there is a design flaw.
I am extremely disappointed in Linksys. I cannot imaging why they would waste hours of my time - and theirs - trying to correct a problem that could not be fixed! This is my first experience with a Linksys product. Anybody can make a mistake, but this is inexcusible.