Slashdot Mirror
Asynchronized Internet Connections?
Zid asks: "I've got a cable modem, and the apartment I live in has a T1. The problem I have is that my cable goes out constantly, and the T1 is shared among the entire complex (200+ people) and it's behind a 3com NAT, so I'd like to be able to have my Linux box (which is a Masquerade box for the cable right now) to be able to automatically switch over to the T1 as a backup when cable goes out. My second question is whether it's possible to use the T1 as the uplink and cable as the downlink since the T1 can upload 4 times faster than the cable can."
In theory this is possibal. However it won't work well.
In theory your linux box just switches to the other connection, no problem. (Detection is a bit of a pain, but can be done) In parctice it doesn't help much. All your connections are to your cable IP address, which no longer reaches you. (it gets routed to your cable company who cannot reach you so they throw it away)
If you have a friend with several stable IP addresses and a good connection, then you can probably tunnel to them (with some work). Otherwise your problem isn't sending data out the backup line, it is getting data to come back over that line without losing connections.
If anyone has a solution please let me know - I'm on a dialup with poor line quality. I have a big problem with programs trying to hold a connction longer then the line will stay up at a time.
Check out http://adsl.contamination.org/how_tos.ht ml. This is for Zoomtown (cincinnati bell) but they use the same cisco, so i bet that the setup is similar.