Win 7 - Dual WAN on Desktop PC - automatic failover?

Windows will never automatically failover or load balance. Any traffic determined not to be local (i.e., destined for the Internet) will use the network connection which specifies the default gateway. If you have more than one default gateway, then Windows will use one network connection exclusively and totally ignore the other. The network connection chosen is the one w/ the highest priority (see Network Connections-->Advanced-->Advanced Settings-->Connections).

In fact, if both network connections use the same subnet (e.g., 192.168.1.x), it will likewise only use one of those network connections exclusively for local traffic and totally ignore the other.

So Windows will *never* load balance, it's just not designed to work that way being a desktop environment. Any such failover and/or load balancing would need to take place on the router. They make dual WAN routers for this purpose and would be the better avenue to pursue (it's a better choice anyway since ALL your devices could benefit, not just that PC).

look for a DUAL WAN router. they usually do auto fail-over

http://www.newegg.com/Product/Product.aspx?Item=N82E168...

I am looking for a non hardware solution.


I am not looking for windows to load balance.

I work from home and I want to have 100% connectivity to the internet 24/7 without a drop in connection.

So, if I have both ethernet and wireless nics enabled.... should I in effect have 100% uptime?

ie. if cable isp goes down... my PC will auto route traffic thru dsl ..and I will notice nothing at all while browsing the web, using internet based apps etc. ?

I suspect it would NOT work the way you want for the simple reason that a loss of Internet connection doesn't (for lack of a better term) "invalidate" the connection. IOW, the fact your cable or dsl dropped (for whatever reason) doesn't make your local network unavailable. From Windows perspective, the connection is perfectly valid. It's just that attempts to certain addresses (Internet addresses in this case) fail. If you're using say, IE, all that's going to happen is IE will return some appropriate error, like "404 not found", whatever. It has no clue it’s because the cable/dsl connection upstream failed.

Now if the connection between the Windows machine and router failed (e.g., failed hardware), that might be a different story. In that case, I’m not sure if Windows would simply “give up” and wait for the connection to be fixed (using that word loosely), or attempt to use the other connection. If I had to guess, I suspect it would just give up and not switch adapters.

What you really need is some piece of client software to monitor your connections locally, then switch adapters when a problem occurs. You could probably do this w/ a batch file using ping and netsh. Perhaps ping some reliable Internet site every 60 secs and if it fails, switch adapters using netsh. Certainly not foolproof though since it doesn’t account for a down website. And how quickly must this detection and switchover occur? It’s just not an easy problem to solve at the client, esp. if you always want accurate, instantaneous results. You can only achieve that at the router! Anything you do at the client is a kludge, at best, and may not work at all.

NOP. you will have to refresh you network connection since they have two different networks and windows will NOT do auto routing.

to simulate it you could disconnect the TV cable from the modem (not the network cable) to see what is involved in switching manually. See if repairing the wireless connection will do the trick or if you have to disconnect the network cable, too.

just found this software; however, not sure if it will work for you:

http://www.nat32.com/

Just test it out by pulling the ethernet out and see how long it takes before you can browse. Typically on Win 7 machines with this setup all current connections are abandoned and new connections start on the highest priority connected adapter (wireless) aka all active downloads fail. So a 98% uptime would be more accurate, but yes windows does this for you even if it is not seamless.

I did exactly this.

I enabled both adapters ...first the cable...then enabled the wireless.

I started my work applications (web based) and let it run for 2 mins.

Then, I unplugged the cable going into my cable modem, simulating a loss of cable signal.

My web apps hung and eventually died. win 7 did not auto failover to routing traffic to the wireless adapter.
(This could be due to the fact that my web apps require SSL connections and probably require me to securely login if there are any network changes.)

However, I also tried opening up websites...and was unable to pull up any sites. I tried this for about 2-3 mins and still nothing worked.

In order to get it to work...I had to DISABLE the LAN adapter... about 1 min after that, I was able to browse the web again.


So, apparently, there is no auto failover...you must manually disable the adapter that went down. Which kinda sucks..

Seems to me it doesn't matter anyway. The chances you would have a failure at the client (failed adapter, port, cable, etc.) are next to nil. The far more likely problem is the loss of one of the broadband connections, which as I said before, is NEVER going to result in any change on the client. As far as the client is concerned, the connection remains perfectly valid, but for reasons it can't determine, certain IPs result in failed connections. Of course, *we* know it's either cable or DSL is down, but the client can't make that distinction. The ONLY solution is to place the responsibility in the router. And that means either a dual-wan router, OR, bring the router to your PC (i.e., your PC becomes the dual-wan router). Anything else and you're fighting a losing battle.

Hi, what about this?(copy from another forum), I don't completly understand, someone make a quide please, I guess I can use 2 wireless cards to make it work


I had made a dual ISP configuration on my windows 7 x64. I would like to share it here with this amazing forum.

I have two ISP's with same bandwidth, one is over wireless and the second over wire. I had configured a static IP address for both of them with same metric and WoW I got the whole bandwidth of both.

How to make your metric equal?
here is the trick. First configure the first ISP with GW metric 25 and the interface metric 1 and the second ISP with GW 24 and the interface metric with 2.

it should be 26 when you run the command in "route print"

I hope this will help some people over the world.

Mike

Go to the wired nic properties tcp/ip settings advanced metric set 10.then go to wireless nic tcp/ip advanced metric 20.