[bluecmd]

Devil is in the details, but the source actually talks against you here:

  This happens because your router or firewall is trying to clean up dead connections. It's seeing that no data has been  transmitted in N seconds and falsely assumes that the  connection is no longer in use.
 To rectify this you can add a Keep-Alive. This will ensure that your connection stays open to the server and the firewall doesn't close it.

In other words: What keep-alive does is that it prevents routers/middle-ware-boxes to forget that the connection exists in the first place. This is not needed on a clean internet connection where everything is treated as stateless and simple routing is everything that is done.

[laumars]

It also says: "if you disconnect from the Internet, your connection will be usable when you reconnect.". The same logic applies if you restart your network interfaces on the server.

I'm open to being proved wrong here, but as I've already said, only been doing this for several years now, so I'd need a counter argument to explain the mechanics of what's allowing the connection to reattach rather than "it's not possible" :)

edit: hmmm, re-reading the latter part of keep alive article I posted, it does seem to imply what your saying. So how come my SSH connections aren't nuked then? Is this just a property of TCP/IP (I'm not a networking guy so ignorant to some of the lower level stuff)

[bluecmd]

Yes, as long as both endpoints (TCP/IP stacks) keep their state it doesn't matter what stuff does between them. Interfaces being one of the things being between stacks. That is what allows for stuff like live application migration as long as you bring the TCP/IP state.

[laumars]

I see. Thank you :)