How can I connect two networks having different ISP's?

Thread Starter

Roshela_kyoot

Joined Oct 6, 2005
8
Good day!

How can I connect two networks having different ISP's to share a single file server.. Both of the networks are in the same building.. What must be done to make the share a single Vine Linux server?

I appreciate any comments or suggestions regarding my post..

thank you..:)
 

studiot

Joined Nov 9, 2007
4,998
Not sure what you are trying to do.

If you are trying to set up this server to upload stuff to different WANs you need to separate network cards one for each network. The router will assign different dynamic IP addresses to each card, or you may need to set static ones. You will also need software to mediate file access conflicts.

If you want your server to allow users on one WAN to access the other WAN check with your ISPs for permission before proceeding. The server needs to be set up as a bridge or connected to a commercial grade router that has a bridge mode.
 

AlexR

Joined Jan 16, 2008
732
As long as the two networks have different network addresses you can connect them through a router. Either a stand-alone router or a linux/unix workstation with 2 network cards.

If the two networks have the same network address you have problems. The simplest solution might be to re-number one of the networks then connect them via a router.

Of course an even simpler (and cheaper) solution is to merge the two networks into one and get rid of one of the ISPs.
 

AlexR

Joined Jan 16, 2008
732
Roshela_kyoot said:
Good day!

Thank you very much for your suggestions and infos..

Sir, regarding installing 2 NIC's on our server, since our file server runs on vine linux, will there be any conflicts between the 2 NIC's or the 2 IP's?

The networks were divided for the reason that our office needs two different ISP's because when one of the ISP's has internet interruption, we can still use the other ISP.

sir, another question is that, will it be possible to create a bridge connection between our vine linux file server and the pc's which are connected to the networks which runs on Microsoft XP?

Thank you very much for taking time in answering my questions..
I don't see any major problems with your setup. The linux machine with the 2 NICs will need to act as a router between your 2 networks. It will have to be set up to pass your local network to network traffic but it MUST block any internet traffic between your 2 networks.
If you were to allow the linux machine to route internet traffic between your ISPs, you would end up with all sorts of nasty routing loops and probably no internet connectivity.
 

studiot

Joined Nov 9, 2007
4,998
Hello Roshela,

There is nothing confidential about the information sent in the private message and I see that Alex has already published it anyway.
We normally like to post solutions and discussion in the thread to help others who may also then benefit. Private messages are for stuff which is - well - private.

Firstly I would take a long hard look at what you are trying to achieve.

The idea of multiple ISPs sounds good, but may just be a waste of money, unless they have different delivery media eg telephone, cable, satphone etc. For ordinary telephone based (broadband) internet faults are normally with the line or exchange, not the ISP so if one is down the chances are another will also be down. The money might be better invested in a more reliable ISP to start with.

Second if all you want is to download internet you don't need to distribute internet via the server at all. In fact this is actually not a good idea. The server should be just another pc connected to the router for security use as a name server. Direct internet connection puts the entire business at risk from hackers. Does your server actually need an internet connection?

I actually manage a sytems in a medium operation where something like you describe is in use, but the internet is definitely off-limits to the server in normal times.

This is a tricky situation to sort out and you really need an on the spot expert. You also need to provide a deal more information, particularly about which way the information flows.
 

Thread Starter

Roshela_kyoot

Joined Oct 6, 2005
8
Thank you very much for the info sir.. We use our internet connections to teach english language to us japanese via VOIP.. so if the internet connection goes off we cant have our lessons.. we are still trying to figure out a way to solve those problems..
 

studiot

Joined Nov 9, 2007
4,998
--------------------------------------------------------------------------------

Thank you very much for the info sir.. We use our internet connections to teach english language to us japanese via VOIP.. so if the internet connection goes off we cant have our lessons.. we are still trying to figure out a way to solve those problems..

I assume you have separate connections to each ISP?

In which case I would recommend you did the following:

1) Set up the separate router for each ISP to restrict local network addresses to non overlapping ranges. This is called setting the scope for each. Set each router as the DHCP host for its respective range.

2) Install additional network cards in each pc so that there is one for each ISP router.

3) For each PC setup the IP so that it sees the preferred ISP as its default gateway and the second one as the alternative. You may also need to set up the pcs with static local addresses to achieve this.

4) This is pretty complicated so get an expert.

5) All your PCs should now be able to receive internet from either ISP, but obviously not together at the same time.

6) You do not need your server to be involved in this system.

7) You do not need anything set up in bridging mode. Every pc will now be able to operate independantly of any other.
 

AlexR

Joined Jan 16, 2008
732
studiot;
Most of what you say is OK but adding a second NIC to each PC is definitely a bad idea. The only way you can do that is if the PCs becomes routers. In any case there is no need. As long as the two routers are interconnected and are running some sort of routing protocol all the PCs should be able to access either network and default to calling their own ISP. If one of the ISPs goes down the routers should redirect all traffic to the other one.

Roshela_kyoot;
As studiot says it can be done. However it won't be cheap and its not something that can be done by a networking novice. You will have to get an expert who knows what he's doing to set up your routers.
 

studiot

Joined Nov 9, 2007
4,998
Most of what you say is OK but adding a second NIC to each PC is definitely a bad idea. The only way you can do that is if the PCs becomes routers. In any case there is no need. As long as the two routers are interconnected and are running some sort of routing protocol all the PCs should be able to access either network and default to calling their own ISP. If one of the ISPs goes down the routers should redirect all traffic to the other one.
Perhaps you would like to elaborate?

With VOIP and perhaps video conferencing you need to set up port forwarding in the respective routers. How would this work?

What is wrong with multiple cards? The PCs don't need to become routers. Windows is capable of handling several cards and choosing the correct one.
 
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AlexR

Joined Jan 16, 2008
732
Perhaps yopu would like to elaborate?
What is wrong with multiple cards? The PCs don't need to become routers. Windows is capable of handling several cards and choosing the correct one.
Yes after more reflection on the problem I do concede that two cards per PC will work and is in fact the most cost effective solution.
My original idea would work but needs 2 professional routers running routing protocols to choose which ISP to use. Using dual NIC cards you can use cheap domestic routers.
 
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