networking dumbass speaks

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Calum
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networking dumbass speaks

Post by Calum »

hello.
i am a complete know nothing about networking.

prospectively i will soon be moving in with two people who each own a windows computer attached to their broadband connection via a little modem/firewall box.

both of their machines are windows xp laptops.
my machines area red hat 9 desktop and a slack 9 laptop. The laptop has a network card and i haven'tbought one for eht desktop yet.

the idea is to get it all so we can all connect to the net atthe sameor different times. both of them have done degrees in computing (i have juststarted mine) but they haven'tgot into linux yet i don'tthink although they're thinking of dual booting.

i am not sure what else the network might want to do, perhaps i might toy with setting the desktop up as a server, perhaps not. maybe files willneed to be shared which brings up user ids, permissions etc.

i am not asking a question here really, you may have noticed, but my only real query is: how should i approach the task of obtaining the knowledge i will need to make me feel comfortable in this new networked environment, and specifically, how will i go about getting the knowledge i need to even comprehend connecting the linuc machines? i know literally nothing about broadband, how to set it up, what info is required etc. I know almost nothing about dialup in fact, i simply use kppp, although i have seen a basic ppp dialup script.

I have the time now so i plan to read the relevant howtos and mini-howtos in /usr/share/doc but what else should i read?

thanks.

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Post by Copperhead »

The first thing you will need to know is what kind of internet connection that you are using, and what protocol. For example, if you are on a cable modem, you are probably using DHCP to get the router to pull an IP address off of your ISP's server. If you are using an xDSL connection, you are probably connecting to the net via PPPoE (point-to-point over ethernet.) In either case, the IP address that your ISP assigns you will become your WAN (wide area network) address, and the IPs that you assign all of your machines behind the router become your LAN (local area network) range.

The quick and easy way to share a connection is to just use the router. I have one of those cheap Linksys "Blue Boxes" that does the trick wonderfully, serving as a gateway/router/firewall. You configure the router and all of your connections/firewall right through a web interface. I then assign all of my other machines (two Red Hat boxes and one Debian machine) IP addresses of addresses 192.168.1.100 - 192.168.1.102. The WAN address is their "World Visible" IP . With these machines, I also firewalled them to give myself some "extra padding", if you will. Since the Debian machine is acting as a web server, I configured the router to use "port fowarding", opening up port 80 on its respective LAN IP, through the router's firewall, and through Shorewall on the box itself. You can do this for all services that you want to have accessible. If you want FTP on that machine, you forward port 21. For SSH, you forward port 22, etc. This actually gives you quite the upper hand in security as well. Instead of the box being read directly by the outside world, you are actually just forwarding data packets through the firewall/router.

The other thing that I like about the Linksys box is that it has a built-in script for dyndns.org. Since I am on a dynamic IP, this saves me a lot of hassle. Its firewalling is decent, but you can never be too safe. It does allow you to filter out a lot of unnecessary content, like ActiveX, JAVA, etc.

If you are feeling adventureous, you can try setting up one of your Linux machines to function as a gateway/firewall/router. I've read a lot of posts on this in this section. I did it on a friend's set up; running Slackware as the firewall/gateway/router, and set up some Linux boxes behind it. I have never tried it with Windows though. In theory, it shoudl all be the same, but with M$, who knows?

O'Reilly has a really good book out called Linux Network Administrators Guide that gives you a very good outline on how to do all of this. In fact, I followed it page by page in order to get my friend's setup going. It explains iptables and ipchains to a tee.

Hope it all goes well for you.

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Post by Tux »

Calum, you mention that the windows boxen are connected to the 'net by a 'little modem/firewall box'. This makes things lots easier for you, as that machine handles the nitty gritty of their broadband (which is probably using PPPoE here in the UK).
I assume, as this is the sane way, that this box is serving the connection on its ethernet device and hopefully providing DHCP services on that interface too.
This leaves only basic setting up on your part:

If it uses DHCP, you need to tell your linux boxes to 'Obtain IP Address via DHCP/BOOTP'. The naming of this option may vary though depending on what configuration program you use. This will make your computer politely ask the server for an IP address and gateway and DNS settings when it boots up and henceforth, everything will be set up for you once it is enabled.

If it (the server) doesnt run DHCP services you will need to enter the aforementioned settings for yourself, namely:
IP Address: Most likely a class C address (ask your friends what to use, becuase IP address clashes cause endless headaches)
Subnet (Mask): 255.255.255.0 (ask your friends what to use again, because else your computer won't integrate with the rest)
Gateway: IP address of 'little modem/firewall box'
DNS: This could be one of two things, the IP address of the server/router or the public IP of your ISPs DNS server and again you will need to ask the guys.

And that should be about it, as far as getting on the internet is concerned. The only other suprise could be that the router/server runs a proxy server in which case you would just have to enter these settings into your 'net using applications' settings.

Once you are actually connecting to the internet and can ping your mates boxes start another thread or Im me and we can do samba.

In fact, I think there already is a samba thread around.

It should all be fairly straightforward Calum; since they have a router/server it is just straight ethernet as far as linux will be concerned.

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Post by Calum »

thanks, guys!
what you say is encouraging, and sounds straightforward, even though i understand little enough of what you said!

that's simply an issue of terminology and getting my head around the current home networking paradigm (as i say i am a total knownothing about past networking other than the history of networking).

Listen, thanks again, i won't be doing this for a few weeks as i am off on holiday soon, but when i come back i think i'll buy that o-reilly book and see what's what. i'll have to figure out how to use my NIC card(s) and all that too i suppose! and find out what kind of interface that mysterious little box is...

i'll post again on this topic in a 3 or 4 weeks.

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Post by X11 »

I think I could make money off people with similar questions. Set up home network solutions for suburban bums with to much money.

The IT industry is about confusing stupid people into giving you lots of money to fix there confusion.

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Post by Void Main »

X11 wrote: The IT industry is about confusing stupid people into giving you lots of money to fix there confusion.
Are you sure you haven't been to college yet? If not you've been to Bill Gates' road course for sure. Here is something humorous along those lines:

http://www.thinkgeek.com/cubegoodies/po ... pair/58fc/

more:

http://www.thinkgeek.com/cubegoodies/posters/despair/

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Post by Tux »

X11 wrote:I think I could make money off people with similar questions. Set up home network solutions for suburban bums with to much money.
That is actually a money making idea I have been playing around with in my mind for the past few days and i think i will actually do it.
Might look good on my UCAS form, showing enthusiasm/initiative in my chosen field or something, they like that bull****e.

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Post by X11 »

Void Main wrote:
X11 wrote: The IT industry is about confusing stupid people into giving you lots of money to fix there confusion.
Are you sure you haven't been to college yet? If not you've been to Bill Gates' road course for sure. Here is something humorous along those lines:

http://www.thinkgeek.com/cubegoodies/po ... pair/58fc/

more:

http://www.thinkgeek.com/cubegoodies/posters/despair/
I have no problem with 80 Billion Dollars, in fact I like the idea.

Good Idea Voidmain.

Im gonna have to get the "Potential" poster.

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