This can break some networking tools, so many of our users will often avoid DNS redirection with the use of alternative DNS services. In Mediacom's case however, the company appears to be using an implementation of deep packet inspection technology that makes this impossible, leaving the company's opt out as the only option. Except it doesn't work.
I think I may have an answer to this, at least under linux. I'm not familiar enough with Windows to know if this will work, but I know that Windows does have a ROUTE command, so it may translate to Windows. My procedure would require a broadband connection
AND A DIALUP CONNECTION SIMULTANEOUSLY. Here is my /etc/conf.d/net file (Gentoo linux)
config_eth0=(
"192.168.123.249 broadcast 192.168.123.255 netmask 255.255.255.248 mtu 1454"
"169.254.1.3 broadcast 169.254.255.255 netmask 255.255.0.0")
routes_eth0=(
"default via 192.168.123.254 metric 2"
"192.168.123.248/29 via 192.168.123.254 metric 0"
"169.254.0.0/16 via 169.254.1.3 metric 0"
)
The reasons for the complexity are as follows...
•The 169.254.x.y is for my network-enabled OTA TV tuner, which INSISTS on coming up with a "zero-config" address.
•I have a dialup account as a backup. The linux "pon" dialup software creates ppp0 and adds a route (metric 1???) statement, which gets over-ridden by the existing route
•In the past, I had to basically tear down eth0 before starting dialup, and then restart it after disconnecting dialup. This meant that I couldn't stay connected with my backup machine during the dialup session.
•My current setup uses "metric 0" (highest priority) for my little LAN and the TV tuner
•The default route (everything else, including the internet) goes via a "metric 2" route
•when I fire up dialup, it does a "metric 1" route, which forces internet access via ppp0, but leaves LAN access alone
Building from this, when a dialup connection is established, run a short script that
•clears the current default route
•sets up a default with metric 2 via eth0 (broadband)
•creates a couple of /32 routes with metric 0, pointing at the outside DNS servers via ppp0 (the dialup connection)
•plan B for linux is to have iptables/netfilter force outbound packets with destination port 53 to use ppp0. I don't know if there is a Windows equivalent.
Because the DNS queries go via the dialup connection, the packets completely bypass Mediacom (unless your dialup connection is via Mediacom as well). Because Mediacom never sees the packets, it can't touch your DNS queries. Dialup is slower, but for small packets like DNS traffic, it's perfectly sufficient. Any comments?