Setting up a network, need some help.

[Feztaa]

Ok, here's the plan. My dad's just gone out and bought himself a new computer (!!), and he needs internet access on it. We already have cable coming into my box, but we need it to go to his, as well. How do I set this up?

Do I have to buy a second network card for my machine, then plug his into mine? If so, how do I configure my box to do that properly, so it works?

Or do I just buy a hub, then plug both machines and the cable modem into the hub, and it will just work? How does it sort out the IP addresses?

Sorry, I'm confused.

Somebody once recommended FreeSCO, but unfortunately that is out of the question in this case: I need my box (the "router", in this case) to run linux, and my dad's box must run windows.

Thanks guys.

[praetorian]

I've heard that just plugging it into a hub is harder to get to work than just using a router but you can give it a try. If you want to go the two nic way, just put two in your computer and setup routing. Setup Linux to be a DHCP server. I'm not sure whatelse it needed cause I've never done it that way. I just rely on my Linksys router to do most of it for me.

[pbharris]

hello,
i had my linux box as a firewall and ipmasqerading. i had two nics, one was for the internet and the other for the hub, which other computers were connected to and then my machine did the rest of it. for ipchains i used pmfirewall to set it up. i have since gotten a hardware router firewall and it does everything now. for iptables i wold use firestarter.

[Feztaa]

i had two nics, one was for the internet and the other for the hub

Ok, now a hub is fine. but if there's only one other computer on the network (just the linux box and the windows box), does it need a hub? Or can I just plug the two computers directly into each other?

which other computers were connected to and then my machine did the rest of it. for ipchains i used pmfirewall to set it up. i have since gotten a hardware router firewall and it does everything now. for iptables i wold use firestarter.

How much do these hardware routers cost?

So you're saying if I got a hardware router, I'd just plug it into the cable modem for internet access, and plug the other two computers into the router? How does it know the information about my internet connection (DHCP server, etc)? How does it know what it's supposed to do? Gah. I should just ask the guy at the computer store what I'll need, apparently two computers sharing the same cable connection is a common problem...

[Schotty]

You have two options that will work. Just plugging them all into the hub isnt going to work. The ISP needs to assign you all an IP that can be used. If you are only supposed to get one IP, then that creates a problem, right ??

No. The commercial routers use NAT to "share" the IP across a LAN. Those are easy and pretty self explanatory. Around the Milwaukee, WI area they can be acquired for 50-200 dependingon quality and amount of LAN ports.

The other option is to setup a proxy on one box and plug that into a hub using a second NIC. Then all of the PCs can use that box as a gateway. I havent used linux to do that for me yet, but if you set it up as a proxy, you can set it up so that they point to that ip for all lookups or you can have a transparent proxy that allows the outside world to be seen without any fiddling.

I have way too much knowledge with NT here in comparison to Linux. But I see that you are resourceful and a quick search on the LDP will get you up and going in no time

Oh if you need NT Software to do this (because you dont have craploads of cash for a router, hub, etc,) mail me directly. I can get ya started. I aint that old to have forgotten how dads can be sometimes,

-- edit -- edit --

Well, ya beat me to the post Routers are the easiest, but the least secure. I have been compromised before. NAT also only covers up through layer 3 protection (on the OSI model, if you even care about tech specifics like that) My reccomendation is this. Buy the router. Play with it get used to it. If you have aspriations to do IT/IS work, youll need to know more complicated ones than this. Next Since you have a PC that is connected to the outside world now, make it a router TOO. That way, if ya screw up, it dont matter. The Original hardware one is still there to prvide the lan access. Granted, thats probably 120 bucks (US $$$ for the router and an extra NIC), but it is the best solution fo the time pressed.

[Feztaa]

You have two options that will work.

Actually, there are three. We could pay the cable company for a second IP, second cable modem, and the whole works... but that's largely out of the question

Just plugging them all into the hub isnt going to work.

I didn't think it would. that's why I'm so confused. If I buy the aforementioned hardware router, how does it automatically know all the NAT stuff?

The ISP needs to assign you all an IP that can be used. If you are only supposed to get one IP, then that creates a problem, right ??

Well, technically it is a problem, but you list solutions. Heheh

No. The commercial routers use NAT to "share" the IP across a LAN. Those are easy and pretty self explanatory. Around the Milwaukee, WI area they can be acquired for 50-200 dependingon quality and amount of LAN ports.

Well I only have two computers to plug into it, so that should allow me to buy a cheap one. The least number of LAN ports I've seen, though, have 5, so that does allow for some upgradeability in the network. Hopefully that'll be cheap.

The other option is to setup a proxy on one box and plug that into a hub using a second NIC. Then all of the PCs can use that box as a gateway. I havent used linux to do that for me yet, but if you set it up as a proxy, you can set it up so that they point to that ip for all lookups or you can have a transparent proxy that allows the outside world to be seen without any fiddling.

Right; I've just realized that dad doesn't need a full connection to the internet, he just needs a web proxy so he can surf websites. This would probably be the easiest solution. Buy a cheap NE2000 compatible ethernet, plug the other computer into it, set up a proxy...

There's another problem, though... he'll need email. I suppose I could just setup fetchmail on my machine to download his mail, then let him connect to my postfix to get his mail... that would be cool!

I'm sure not going to get a hardware router, that's too easy. I want to learn!

I have way too much knowledge with NT here in comparison to Linux. But I see that you are resourceful and a quick search on the LDP will get you up and going in no time

Sounds good.

Oh if you need NT Software to do this (because you dont have craploads of cash for a router, hub, etc,) mail me directly. I can get ya started. I aint that old to have forgotten how dads can be sometimes,

Thanks much

I don't think I'll need NT though, I'll be using Linux for all "nontrivial" systems (ie ones not used by my dad, who'll be using Win98).

Well, ya beat me to the post Routers are the easiest, but the least secure.

I'm not terribly worried about security. My Linux box has security up the yin-yang, and my windows box will be behind my linux firewall, not to mention it'll have it's own little firewall (ZoneAlarm, it's the best for windows), so it'll be fairly secure. Plus, it's a fairly low-profile site (not like microsoft.com or anything), which means there should be very little attention paid to it as far as hacking goes.

I have been compromised before.

Which is weird, because I used Windows for 7 years with no firewall and I was never hacked...

NAT also only covers up through layer 3 protection (on the OSI model, if you even care about tech specifics like that) My reccomendation is this. Buy the router. Play with it get used to it. If you have aspriations to do IT/IS work, youll need to know more complicated ones than this. Next Since you have a PC that is connected to the outside world now, make it a router TOO.

Now I'm confused. I need to make the router and my box connected to the internet at the same time? How's that, I only have one cable modem. The whole point of this is to get both computers sharing the same connection...

That way, if ya screw up, it dont matter. The Original hardware one is still there to prvide the lan access. Granted, thats probably 120 bucks (US $$$ for the router and an extra NIC), but it is the best solution fo the time pressed.

Well I'm not really pressed for time on this. My dad's lived for 46 years without the internet, he'll live without it for another few months if neccessary. My only time restriction is that I have to get it done before I graduate high school and move to university in 7 or 8 months.

[praetorian]

The router knows all this NAT stuff because the program is stored in the router and the router has a certain amount of memory that is used record MAC addys too.

[Schotty]

I knew that Network + Cert would come in handy

Okay lets se here ...

<Clip> didn't think it would. that's why I'm so confused. If I buy the aforementioned hardware router, how does it automatically know all the NAT stuff?

Well, it tracks whos asking for what and when the reply is recieved it goes through the tables to send it to the proper PC


<Clip> Well I only have two computers to plug into it, so that should allow me to buy a cheap one. The least number of LAN ports I've seen, though, have 5, so that does allow for some upgradeability in the network. Hopefully that'll be cheap.

Mine is a one port. WAN and LAN. If you have a switch or a hub thats the cheapest. When they first started selling them in my area, I grabbed one for 150. The 4-porters were 200-300. Of course its a hell of alot cheaper now


<Clip>Right; I've just realized that dad doesn't need a full connection to the internet, he just needs a web proxy so he can surf websites. This would probably be the easiest solution. Buy a cheap NE2000 compatible ethernet, plug the other computer into it, set up a proxy...

That will work.

<Clip> There's another problem, though... he'll need email. I suppose I could just setup fetchmail on my machine to download his mail, then let him connect to my postfix to get his mail... that would be cool!

The proxy will alow for pops and imap boxes to be accessed. Just different ports

<Clip>I'm sure not going to get a hardware router, that's too easy. I want to learn!
Now I'm confused. I need to make the router and my box connected to the internet at the same time? How's that, I only have one cable modem. The whole point of this is to get both computers sharing the same connection...[/quote]

That is easy actually think this way wan->Linksys Router-> Lan. Now on the lan you can make another lan or virtual hub (the PC router). Thats what I am doing slowly in my spare time (which is barely). That way my roommates arent getting on my ass for "the internet is broke". I want to sell my Linksys off, thats why (need the $$$)

<Clip>Well I'm not really pressed for time on this. My dad's lived for 46 years without the internet, he'll live without it for another few months if neccessary. My only time restriction is that I have to get it done before I graduate high school and move to university in 7 or 8 months.

Well, then have fun It shouldnt take you more than a week to figure it out. I just started last friday on my box and it is coming along, slowly but surely. I bookmarked the LDP docs on linux.com for my router help. Feel free to mail me directly with any questions.

Also, before I forget. My to be router box is harddiskless. I am using one of those secure linux distros that boot off of CD and no system stuff can be modified. It seems to be a pretty cool idea, especially if it works. Essentially I build the system and burn it on CD (meaning no hacked config files). Makes security on that box easy.

[pbharris]

Ok, now a hub is fine. but if there's only one other computer on the network (just the linux box and the windows box), does it need a hub? Or can I just plug the two computers directly into each other?

You would need a cross over cable or if you have 10base2 (coax) then a direct connection is the only option.

How much do these hardware routers cost?

mine was around $100.00 US

So you're saying if I got a hardware router, I'd just plug it into the cable modem for internet access, and plug the other two computers into the router? How does it know the information about my internet connection (DHCP server, etc)? How does it know what it's supposed to do? Gah. I should just ask the guy at the computer store what I'll need, apparently two computers sharing the same cable connection is a common problem...

on mine it needs to be setup to receive DHCP or PPPoE and i can be set up as a DHCP server.

[Rastar]

All good dialog but as I just mentioned in another post here is what I would do.

Purchase a Linksys (or your favorite brand) Cable/DSL router.

Configure the router to do the negotiations between for ip address (dynamic I assume).

Assign each computer a static IP address
For Linux netconfig
For windows start, control panel, network configuration, I think it is under the tcp/ip settings.

The router now knows that box A (linux) is ip address XXX.XXX.XXX.XXX and box B (windows) is ip address XXX.XXX.XXX.XXX get rid of dhcp on both machines and the router handles it. If you are surfing on your pop's computer while hosting a game on your linux box the router allows you to set specific ports available
Common ones
80 (so apache will work)
23 (ssh?)
21 (telnet?)
blah blah.

The router will run you around 100 dollars plus a couple of cat 5 cables depending on which model and where you live.

Good Luck, there is a PET for hooking up to a linksys router. Too the point but I think helpfull.

Rastar