Results 1 to 7 of 7

Thread: Newbie needs help with ADSL setup

  1. #1
    Associate
    Join Date
    Apr 2006
    Posts
    16

    Red face Newbie needs help with ADSL setup

    Hi all

    Bit of a clueless Linux tinkerer, but keen to learn more so any help / suggestions welcome.

    Here's my problem:

    I have 4 port ADSL modem for internet connection, 1 Linux machine (mine) and 2 windoze machines (family). I want to set up a little home network where everyone has access to the internet (shares the ADSL connection) but also access to each other's machines via SMB/SAMBA.

    The simplest setup I can imagine would be the following:

    Internet
    !
    ADSL Router
    1 2 3 4
    ! --- eth0
    LinuxBox
    ! --- eth1
    Hub
    1 2 3 4
    ! !
    WindozeBox1 WindozeBox2


    So ADSL Router acts as internet connection to Linux box on eth0. Linux box then shares via NAT and the Hub to the Windoze boxes. eth0 on LinuxBox is dhcp configured, eth1 is 192.168.1.1 and windoze machines are 192.168.1.2 and 192.168.1.3

    I think this would work... problem is I don't have the hub. No problem to buy one but it seems that I have four unused ports in my router? Can I not use them instead of the hub as follows:

    Internet
    !
    ADSL Router
    1 2 3 4
    ! ! !
    LinuxBox WindozeBox1 WindozeBox2

    I have tried this set up, configuring WindozeBox1 to use DHCP and it works fine for WindozeBox1 to see the internet, but it can't see LinuxBox.

    So it seems to me that this setup allows all the machines plugged into the router to share the internet connection but not an internal 192.168.1.0 network as well. Is my assumption correct?

    Or, is there some way I could configure the router to act as a DHCP ADSL modem to LinuxBox out of port 1 and have the other ports acting as simple network hub / switch between LinuxBox and WindozeBoxes?

    Hope it's not too confusing. To put it simply, all I'm trying to achieve is the following:

    1. Not have to buy a switch / hub
    2. Windoze & Linux machines to see each other on internal TCP/IP network independent of internet connectivity
    3. All to have internet connection
    4. Safety for windoze boxes. I'm not a windoze security man and am nervous about having them exposed directly to the inernet.

    Any help, comments, thoughts appreciated.

    Cheers
    James

  2. #2
    What is the model for the ADSL modem?
    My crime is that of curiosity. My crime is that of judging people by what they say and think, not what they look like. My crime is that of outsmarting you, something that you will never forgive.

  3. #3
    Associate
    Join Date
    Apr 2006
    Posts
    16

    Question

    It's a Marconi. Not sure if it is that well known. Seems to be the local model used by our local monopoly telecommunications agency.

    It appears to be quite configurable, though. You can log into it via web-browser and fiddle with all the settings.

    Is that helpful?

    thanks
    James

  4. #4
    Quote Originally Posted by axxis
    It's a Marconi. Not sure if it is that well known. Seems to be the local model used by our local monopoly telecommunications agency.

    It appears to be quite configurable, though. You can log into it via web-browser and fiddle with all the settings.

    Is that helpful?

    thanks
    James
    You say that the Windows box gets an IP address. Is it a public or a private address?

    To my understanding, there are 2 possibilities. Firs t one is your modem acts as a router/switch, receiving a public IP address and then handing out private addresses to your home computers. If this is the case, your setup should work fine. The other case would be that your modem just acts as a bridge and hands out a public address to your computer. If that is the case, then you need to modify your setup to add a home switch/router, since is unlikely your isp would hand you more than one public IP address.

    HTH.
    My crime is that of curiosity. My crime is that of judging people by what they say and think, not what they look like. My crime is that of outsmarting you, something that you will never forgive.

  5. #5
    Associate
    Join Date
    Apr 2006
    Posts
    16

    Red face

    >>You say that the Windows box gets an IP address. Is it a public or a private address?

    If I configure windows box for DHCP & plug it into ADSL router, it gets a public address. Currently, I have it set up with a static private address and connected directly to eth1 on my linux box with NAT giving it access to the internet.


    >>To my understanding, there are 2 possibilities. Firs t one is your modem acts as a router/switch, receiving a public IP address and then handing out private addresses to your home computers. If this is the case, your setup should work fine. The other case would be that your modem just acts as a bridge and hands out a public address to your computer. If that is the case, then you need to modify your setup to add a home switch/router, since is unlikely your isp would hand you more than one public IP address.

    I think your first possibility is probably the correct one- my router acting as a switch, receiving a public IP address and handing out private ones to the home computers. If this is the case, how can I get my home computers to talk to each other? I presume they will get a different private address each time they connect? Say the router assigns 192.168.1.1 to my linux box and 192.168.1.2 to my windows box, if I ping 192.168.1.2 from my linux box, will that work? Can I force the router to always give out the same private addresses?

    I'll fiddle around and see if I come up with more information. Unfortunately I tried to upgrade to FC5 last night and the kernel is panicking.... so there may be a delay here ;-)

    Many thanks for your help, though. Any further suggestions appreciated.

    james

  6. #6
    If your windows box gets a public IP address from the ADSL modem, then whatever you connect to the ADSL modem will get 1 public IP address, be it the linux box or the windows one.

    From what I understand, what you want to do is have the linux box connected to the modem, and have the Windows machine connected to the Linux one, doing NAT. If this is the case, try turning off the modem before connecting it to the linux box, so that it releases the public IP address. Then turn it back on while connected to the powered-off linux box, then ring up the linux box. If the linux box still does not get an IP address off the modem, it might be that your ISP is keeping track of the MAC address connected to the DSL modem. You might need to forge the MAC address on the Linux box.

    HTH
    My crime is that of curiosity. My crime is that of judging people by what they say and think, not what they look like. My crime is that of outsmarting you, something that you will never forgive.

  7. #7
    Moderator
    Good Guru
    Schotty's Avatar
    Join Date
    Jul 2001
    Location
    Milwaukee, WI
    Posts
    5,760
    Quote Originally Posted by axxis
    Can I not use them instead of the hub as follows:

    Internet
    !
    ADSL Router
    1 2 3 4
    ! ! !
    LinuxBox WindozeBox1 WindozeBox2
    Yes but you MUST do one thing before setting up DHCP on the linux rig: disable DHCP on your NAT router. Setup the router with a static IP and your linux DHCP server similarily so:

    192.168.1.1 - Router
    192.168.1.2 - DCHP, Samba Linux rig
    192.168.1.3-254 - Client computers

    This way you avoid the DHCP conflict. Ensure that you setup DHCP to dole out DNS and gateway info too, and that would most likely be your routers' IP.

    I have done this many o' times without issue.

Similar Threads

  1. Unable to setup a NIS server setup on CentOS system
    By swatidas in forum Linux - Software, Applications & Programming
    Replies: 1
    Last Post: 01-19-2010, 02:42 PM
  2. Newbie - Trouble finishing Openfire setup wizard
    By sabkuchindia in forum Linux - Software, Applications & Programming
    Replies: 1
    Last Post: 04-20-2009, 05:41 PM
  3. need help with pci adsl
    By cletus in forum Linux - Hardware, Networking & Security
    Replies: 11
    Last Post: 05-11-2004, 02:05 PM
  4. Redhat 9/internet setup/newbie/help
    By quigley0 in forum Linux - Hardware, Networking & Security
    Replies: 11
    Last Post: 07-16-2003, 07:50 AM
  5. newbie needs basic setup help!
    By muppet-boy in forum Linux - Hardware, Networking & Security
    Replies: 7
    Last Post: 11-08-2002, 11:50 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •