Networking 101

[PerpetualVice]

I'm completely new to both Linux and networking but I've been working on this for about a day and a half now and I've been able to download and compile showeq. Now its come down to the last problem and this one has been giving me some trouble. To avoid flames YES i have read the faqs, searched the board, searched other boards (linux.org, etc) and fiddled around with my network but I have STILL been unable to get thins working correctly. Currently my network setup is thus:

[Internet, (given a static IP by my apartment complex)]
||
[Hub, Hawking Technologies 4-port Mini Hub]
|| ||
[Linux box] [Win box]

I'm at a complete loss as to how to configure this and all my research has begot me was more confusion. Do i use IP masqueraiding? IP tables? Do I need a router?

If anyone could please help me, mail me or post here I would GREATLY appriciate it. Otherwise I'm doomed to fiddle endlessly.

Thanks

~PV~

PS. Regarding the hub i have the internet connection plugged into slot 1 which acts as an "uplink." Quite honestly I have no idea the pertinence of this. For now I am able to get on the internet and play eq but only one computer is connected at a time (depending on which i start up first). Also I am unable to ping either box from its counterpart.

[whitewolf3399]

You neglect to mention just what kind of service is provided by your complex... DSL? Cable? How are you feeding that to the hub?

Just guessing from the info you've provided it sounds like you're using a modem (DSL or Cable). What you need is a router capable of NAT'ing the public static ip you're getting from your provide to a private address used by your home network.

The linux box is more than capable of doing this if you have a pair of NIC cards installed, check the various linux help forums for routing and firewall topics. The other options are to use a hardware router or to setup your windows PC as the router, though that is not the ideal solution IMO.

Best (and cheapest) setup your linux box as the router, place it between whatever modem you have and the hub, you should be golden.


--Tom

[Resiliant]

I believe the problem here is subnetting. In order for the SEQ machine to see the traffic to the EQ machine they must be on the same subnet. (This is assuming that you really have a HUB and not a SWITCH or ROUTER).

The simple problem here is that your ISP has assigned you ONE IP address..not two. You have ONE machine that is 'legal' on the subnet they have assigned you to. Hence, you have only one machine that can be used at one time.

The thing to do is, simply, get another IP for your SEQ machine, or choose one yourself that is not currently used on your subnet.

For example, if your assigned IP is 234.51.119.88, and your subnet mask is 255.255.255.0 This implies that your subnet is 234.51.119 (The mask determines which portions of the IP address identify the subnet, and which are used to identify individual machines.) First, you cannot have two machines on the same subnet with the same IP. You can NOT simply assign your SEQ machine 234.51.118.88. It needs to be 234.51.119.x where x is any number OTHER than 88 (and other than any number assigned to any other NIC on your subnet.)

SO... The proper procedure is to contact your ISP and obtain another IP address. Barring this, you can simply randomly choose an IP address, and hope that a) it is not currently in use, and b) it will not be used in the future... in which case you may get a call from your ISP inquiring if you have mis-assigned your IP address, and risk being discontinued if you do not change it.. they have the right to assign IP's as they see fit.

A simple solution (and the one, in fact I use... and one that is extremely useful if you have DHCP address assignment) is to purchase one of the extremely reasonable ROUTERS that act as a local DHCP server, and establish your OWN subdomain (This is what Whitewolf is referring to NAT = Network Address Translation, or turning the IP address your ISP gave you into one of several on your subdomain -- its kind of like Magic :), and place it upstream of your EQ/SEQ HUB. (Do NOT simply plug the EQ and SEQ machines into the router... this WILL NOT WORK as previously described).

The simplest test to determine if two NICs can talk to eachother is to simply 'PING' the other machine. Thus, given the above example, if you have been assigned the two client subnet addresses '88' and '23', and if you are on the '23' machine, the command:

ping 234.51.119.88

should successfully ping the '88' machine, and if you are ON the '88' machine,

ping 234.51.119.23

should ping '23'

If the pings both work, then chances are (if you realll REALLY have a hub and not a switch or router) SEQ will work.

:)

[fryfrog]

if you don't need internet for your seq box, just issue an "ifconfig eth0 up" and then start showeq. it doesn't have to actually have an ip address to sniff. of course, getting updates would be a bitch ;)

[PerpetualVice]

Extremely helpful on all accounts. Thanks for all your input, I will be putting the information to good use. Hopefully the next time you see me here I will have everything figured out.

~PV~

PS. In reference to what kind of service I have i believe it is a T3. My apartment is currently run by complete jackasses though and it wouldnt surprise me in the least if we were lied to through incompetance.

[whitewolf3399]

Gak!!! Leave it to the expert to find the obvious answer... You would think I would have realized that no ip was needed since my config is running bridged, and neither card has an ip

/em wacks himself in the forehead


--Tom

[fryfrog]

hehehe :)

also, don't forget you can't use a switch (or a hub that says its a hub but is really a switch)