internet + file sharing = HELP NEEDED! How should I setup my network settings?

[motulist]

I need help finding the correct settings here. I want a computer which uses a PPP internet connection on DSL, to also be able to do local file sharing to my laptop. Currently I can connect to the internet, or I can share files from my hard disk over my local network, but I can't do both at the same time.

Here's my setup and how I want things to function:

                connect to net via PPP DSL
                share files locally to Mac B 
                Mac A
 DSL modem         |             
          \        |        __________Mac B
           \       |       /          access Mac A's shared disk
            \      |      /           connect to net via neighbor's airport
              ethernet hub
              (aka switch)

Things I've tried:

1) When Mac A's network is set to have TCP/IP use PPP, then I can connect to the net via DSL, but it cannot do file sharing to Mac B.

2) When both Mac A and Mac B are set to have TCP/IP use DHCP, then Mac A can share its files to Mac B, but it cannot connect to the net via DSL.

3) If Mac A connects to the net via DSL using PPP and then I turn on file sharing, and then on Mac B I manually type in the address that Mac A's file sharing screen says it can be reached at. That results in Mac B connecting to Mac A's shared disk by networking over the internet! Which is obviously out of the question.

4) At some point (I forget what the settings were) I managed to have to Mac A sharing its files with Mac B and also had both connected to the net at the same time, but Mac B was connected to the net via Mac A's internet sharing. But my DSL connection is very slow, and having internet sharing turned on seemed to cut my bandwidth to each computer in half, regardless of if the other computer was actually sending or receiving any internet data or not. So that setup is unacceptable.

note: Mac B seems to be able to connect to the net via my neighbor's airport regardless of the network settings I've tried so far.


How the heck do I get this to work?! Is there some sort of submask or proxy setting I need to change? Help!

 

[yellow]

FYI, a hub and a switch are not the same thing.


AFAIK, your Mac must be NEXT in line from the DSL router, then sharing out it's internet connection via Internet sharing over Airport or Firewire. Then you shouldn't have any issues. I believe the hub is superfluous.

 

[motulist]

FYI, a hub and a switch are not the same thing.


AFAIK, your Mac must be NEXT in line from the DSL router, then sharing out it's internet connection via Internet sharing over Airport or Firewire. Then you shouldn't have any issues. I believe the hub is superfluous.

No, I have the setup diagramed above and my mac connects to the DSL with no problem. I'm using an ethernet switch, but I called it an ethernet hub also because that's how many people know it.

And even cooler is that with the setup diagramed above, any Mac on the network can be directly connected to the DSL net connection simultaneously rather than just having one Mac connected to the net and the other's just piggybacking via that first Mac's internet sharing services.

But I need to find a way to have them both connected to the net in a fast way and still have file sharing between them locally.

 

[yellow]

No, I have the setup diagramed above and my mac connects to the DSL with no problem. I'm using an ethernet switch, but I called it an ethernet hub also because that's how many people know it.

I never said that it won't work. I'm saying that you cannot have your Mac act as a router AND get it's network connection via the same cable. I don't believe "Internet Sharing" is set up to work like that.

Anyway, let's educate them right now.

A hub is NOT a switch. A switch is NOT a hub.

There.. that's done.

You might get more milage finding a router that can connect to PPP/DSL, assuming one exists.

 

[motulist]

you cannot have your Mac act as a router AND get it's network connection via the same cable.

Oh, I think I see. By "act as a router" you mean share its files, correct? So you're saying it's not possible to have an ethernet cable going from Mac #1 that sends carries its internet connection and also sends file sharing traffic locally to another Mac in the room, all connected by an ethernet switch. Do I understand that correctly?

 

[yellow]

Perhaps I'm not understanding what you're doing.

From what your diagram shows, in order to get a 'net conneciton, you have to perform some sort of PPP connection on Mac A, correct?
Or is all of this handled automagically via the DSL modem?

 

[motulist]

Perhaps I'm not understanding what you're doing.

From what your diagram shows, in order to get a 'net conneciton, you have to perform some sort of PPP connection on Mac A, correct? Or is all of this handled automagically via the DSL router?

Mac A is getting its net connection over DSL via PPP.
Mac B is getting its net connection from a neighbor's wireless connection which is solely unrelated to the net connection that Mac A uses.

So these two separate computers are running their two separate net connections via two different ISPs and two different networking technologies.

At the same time I want Mac A to share the files on its hard drive with Mac B directly over my local ethernet connection through the ethernet switch.

 

[motulist]

I suppose a more precise diagram would look like this:

+ = file sharing data
- = internet traffic
((( = wireless



                
                Mac A
 DSL modem         |+                           
          \        |+          +++++ Mac B -----(((   airport   (((-----
           \       |+        +                        to separate
            \      |+      +                          net connection 
              ethernet switch

 

[yellow]

Ahhhh....

This might be a problem.

In order to do this, you will have to 1) not use your neighbor's wifi connection (which you shouldn't be doing without their knowledge anyway.), and use Internet Sharing from Mac A.

Frankly I don't think you should use Internet Sharing via Mac A through an ethernet cable & the switch because it might/will probably act as a router for any computer on the DSL subnet. That would be bad. Your DSL provider would be quite upset. And your Mac isn't designed to do that. Meaning, any computer that comes onto the DSL network and asks for an IP address might be given one by Mac A.

Which means you would need to use Internet Sharing via firewire (and a firewire cable) between the 2 Macs in order to get file sharing going, and keep having a 'net connection.

Which gets back to my earlier post.. the hub becomes superfluous.


DSL Modem <-PPP-> Mac A <-Internet Sharing (via Firewire)-> Mac B


What you've diagramed won't work, because Mac B has a different IP address and a different subnet. So, hooking it up with a network cable doesn't do anything for you, unless of course it's got multiple NICs. Any connections to it will be via your stolen wifi from your neighbor and in order to file share, their router needs to have holes poked in it's firewall. Which you're not going to be able to do. So.. either you switch both Macs to steal wireless so they are on the same subnet, or you switch both Macs to use your DSL-PPP.