LinuxQuestions.org
Welcome to the most active Linux Forum on the web.
Home Forums Tutorials Articles Register
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Networking
User Name
Password
Linux - Networking This forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.

Notices


Reply
  Search this Thread
Old 07-18-2003, 01:44 AM   #1
chadtce
LQ Newbie
 
Registered: Jul 2003
Location: Kuantan, Pahang, Malaysia
Distribution: Slackware 9.0
Posts: 6

Rep: Reputation: 0
Communicating Class A and Class C Networks


Hi there,
Can anybody explains, how Class A and Class C networks interconnected? I'm stuck with that since I try to connect 'em using linux ip aliasing method. Is it posiible?

I'm on Slack9 and I hope there's some suggestions regarding that.
 
Old 07-18-2003, 09:22 PM   #2
chadtce
LQ Newbie
 
Registered: Jul 2003
Location: Kuantan, Pahang, Malaysia
Distribution: Slackware 9.0
Posts: 6

Original Poster
Rep: Reputation: 0
I wanna make this happen in my network:

[1][the internet]
|
|
|
[2][a web-caching server]
192.168.0.1:4480
|
|
[100mbps Switch]
| | |
| | |----[3][the Slackware router+iptables with 1 NIC and two IP alias]
| | 192.168.0.103 [eth0]
| | 192.168.1.1 [eth0:0]
| |
| |-------[4][Win98 clients from room1]
| 192.168.0.xxx
|
|-----------[5][Win98 clients from room2]
192.168.1.xxx

My question, how could I make the these subnets communicate each other?
My priority is to make all traffic from [5] should go through [3] before it goes to [2].
Is this going to happen or "just forget about it?"
 
Old 07-20-2003, 08:04 AM   #3
dorian33
Member
 
Registered: Jan 2003
Location: Poland, Warsaw
Distribution: LFS, Gentoo
Posts: 591

Rep: Reputation: 32
You need to set proper gateway for [5].

But the configuration you have described is very strange for me (apart from the poor drawing :) because:
1. usually router is the computer which is placed between "world" and LAN
2. router should have 2 NICs not connected to the same switch (or hub) - on the other case the firewall won't be able to play correctly
3. the cashing servers are usually inside LAN so they don't connect to the internet directly (but via router)
4. why the cashing server has not an public IP (or it has got but not shown?)
 
Old 07-20-2003, 10:08 PM   #4
chadtce
LQ Newbie
 
Registered: Jul 2003
Location: Kuantan, Pahang, Malaysia
Distribution: Slackware 9.0
Posts: 6

Original Poster
Rep: Reputation: 0
Quote:
1. usually router is the computer which is placed between "world" and LAN
Is this means that the web-caching server should be connected to the router? The router acts as a gateway to the outside world.
Quote:
2. router should have 2 NICs not connected to the same switch (or hub) - on the other case the firewall won't be able to play correctly
I'm using IP aliasing for that to create some sort of two NICs. Is it possible or IP aliasing is just for anything else? I'm misinterpreted the term IP aliasing maybe...
Quote:
4. why the cashing server has not an public IP (or it has got but not shown?)
The web-caching server is not having any public domain since it is used to speed up LAN internet access purposes only. It is not proxying apache to the outside world.
 
Old 07-21-2003, 12:02 PM   #5
dorian33
Member
 
Registered: Jan 2003
Location: Poland, Warsaw
Distribution: LFS, Gentoo
Posts: 591

Rep: Reputation: 32
1. suggested topology is:
Code:
internet ("world")
    |
    |  1st NIC with external IP
    |/
router (iptables) 
    |\
    |  2nd NIC with internal IP (f. ex. 192.168.0.103)
    |
switch
    |--- local server (www proxy)
    |--- box 1
    |--- box 2
This way you can really separate internal LAN from the world (assuming correct firewall)

2. IP aliasing is nothing as far as security. Although 192.168.x.x are theoretically "non-routable" there is a lot of attacks with the packet which are crafted with source and/or destination IP addresses from this range.

4. So your drawing is incorrect - the line from internet goes to the web-caching server and next (another line) goes from server to the switch. To get such topology you need 2 NICs (like above)
BTW: public IP <> public domain
 
Old 07-21-2003, 03:24 PM   #6
Half_Elf
LQ Guru
 
Registered: Sep 2001
Location: Montreal, Canada
Distribution: Slackware; Debian; Gentoo...
Posts: 2,163

Rep: Reputation: 46
I have the exact (or so) architecture and it's working well.
The only difference is that I have a box acting as a router in the middle of all box. This "router" does NAT to internet AND external connection, so both subnet can talk.

Just do some search 'bout NAT, it's a great thing.
 
Old 07-22-2003, 11:17 AM   #7
dorian33
Member
 
Registered: Jan 2003
Location: Poland, Warsaw
Distribution: LFS, Gentoo
Posts: 591

Rep: Reputation: 32
Quote:
I have the exact (or so) architecture and it's working well.
The only difference is that I have a box acting as a router in the middle of all box.
Sorry, but above sentences are contradictory.
 
Old 07-22-2003, 05:51 PM   #8
Half_Elf
LQ Guru
 
Registered: Sep 2001
Location: Montreal, Canada
Distribution: Slackware; Debian; Gentoo...
Posts: 2,163

Rep: Reputation: 46
LOL sorry my second sentences is bad. I meant that instead of having a switch thhe this switch connected to a linux router, I ONLY have a linux router ( a cool P120 with 4 networks card in it ). 2 of these network card are connected directly to computers, 1 of these is connected to an hub and the last to internet.
So :
INTERNET
|
|
|-------(Alone Computer) 192.168.0.2
(ROUTER)
|-------(Alone Computer) 192.168.0.3
|
|
|
(SWITCH)-------- 192.168.1.2
|------------ 192.168.1.3
|------------ 192.168.1.4

Is it clear now?
 
Old 07-23-2003, 02:39 AM   #9
born4linux
Senior Member
 
Registered: Sep 2002
Location: Philippines
Distribution: Slackware, RHEL&variants, AIX, SuSE
Posts: 1,127

Rep: Reputation: 49
geez. how many machines in each subnet are we talking about here? 200? 250?
 
Old 07-23-2003, 09:40 AM   #10
Half_Elf
LQ Guru
 
Registered: Sep 2001
Location: Montreal, Canada
Distribution: Slackware; Debian; Gentoo...
Posts: 2,163

Rep: Reputation: 46
3 in one, 2 in another I think
 
Old 07-23-2003, 01:36 PM   #11
dorian33
Member
 
Registered: Jan 2003
Location: Poland, Warsaw
Distribution: LFS, Gentoo
Posts: 591

Rep: Reputation: 32
Sorry but I still don't understand.
As I wrote - typical router has 2 NIC so it is 2-port device.
How many ports the router has? Is it a multiport device?
 
  


Reply



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off



Similar Threads
Thread Thread Starter Forum Replies Last Post
Implementing a vector class from a list class purefan Programming 9 04-14-2005 10:48 PM
PHP: how to use a method from a class in the same class ldp Programming 5 09-17-2004 09:52 AM
BlackBox.class & VerifierBug.class virus ??? dalek Linux - Security 4 02-29-2004 08:55 AM
Inheriting class members (Qt C++, QApplication class) jtshaw Programming 2 01-15-2004 11:52 AM
c++ : regarding (inheritence)base class and derived class edreddy Programming 6 07-31-2002 06:33 PM

LinuxQuestions.org > Forums > Linux Forums > Linux - Networking

All times are GMT -5. The time now is 09:24 AM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration