Topic: SME server and three NICs (two ISPs and one LAN)

[ivankr]

Is there any possibility to use E-Smith to connect to two Internet Service Providers? I need to have one active connection to ISP1 and reserved connection to ISP2 (it is activated if the first connection is down) for my LAN.

I heard that 3 NICs is not normal for SME, is it right?

Is there any tool for switching between ISP-channels ?

All the NICs is ethernet

thanks!

[ivankr]

Pleeeeease!! help!
         

[anand]

hmm... this sounds real interesting, i would also like to know if its possible.

[arne]

Yes, from a principle point of view, it should be possible.

It is of cource not supported by the standard functions of the SME server.

The way of doing it should be to make a "server only" installation without a firewall. Then you have to set up your own networking and configuration scripts that will maintain trafic to/from the 3 Network adapters.

It should be possible to make such a configuration script if needed, but there vould also be some things about it to work out, before it works. Its a typical project that can not be solved on the paper, it has to be tried out.

To set up an alternative way out to for outgoing trafic should not be to difficult. To set up the way in to the server from 2 different connections might be a bit more difficult, but I guess it can be done.

One oter issue - I belive one configuration script basecely only will only be able to rout the outgoing trafic to one of the network cards. You will then have to run a aternative config script to change over to the other Network adapter for trafic out.

One way around that - I believe thet it could be possible to configure two ips on the internal card so if the clients is set up with gateway ip no 1 the trafick will be passed out to the one ISP and gatway no 2 to the other.

I believe that there is no automatic way to switch between thos two ISP.

As mentioned - theese things has to be tried, it might be a lot of "small things" that will have to be solved before it run.

Please spesify a bit bether if it is a question of outgoing trafick or incommeing trafick (server functions.)

[arne]

I have red the question once more.. It seems like the situation is that there is two ISP vendors with two not enough realible connection lines so it is just a question of sharing a connection out in a reliable way.

But: How do you manage the connection out, is it a connection where you just receive the ip via ethernet to the network adapter ? Is it a question of operating one or more PPPoE adapters ?

Would it be good enough to make such a arrangement so that the administrator or anyone with such rights could run a script like "connection1" or "connection2" or does it need to be "full automatic" ?

[anand]

hmm.. can we combine 2 connections and use their combined speed for the sme server and the network under it ?

edit: both connections being ethernet.

[meanpenguin]

The easiest way is to buy an external router that supports this.

Search for Nexland Pro800turbo
DMay has a short entry in his Hardware Forums..

I belive Linksys just came out with one as well
but I can't seem to find the reference.

Ed

[anand]

well hardware is excellent, but what about places where u don't get them/ too expensive to afford ? just like mine.

[arne]

A standard firewall/roting sentece/rule for setting up a cheared ineternet connection could look like something like this:

iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE

When you set up this rule you will have to specify which ethernet card that is the outgoing connection. It's nothing dynamic here, it's just static.

If you on the other hand have two scripts one thet specify the one card and one the other, it should be possibly to choose the outgoing connection by rynning the one script or the other. (And this could be done remootly from any workstation.)

I think the cheap and easy solution to this problem vould be to use 2 gateway PC's instead of 1, each connected to one ISP. I have used Pentium 166 in such a role and have worked ok, so this can be done with rather cheap hardware (and free software.)

Then you can chuse if you are using the one or the other connection by specifying the one or the other PC as the gateway. Of couse you could also run 50 % of the clients on one gateway and 50 % on the other. If one line stop you will have the oportunity to reconfigure the gateway setup on the client so its using the other line. Yuo will at lest have "internet connection" as long as one of the lines work.

To set up a double set of gateway PC's should be a quick and simple solution with really no problems.

To set up a SME gateway server with 3 network interfases would be, I think something rather "tricky and unstandard".

By the way there is also other Gateway softwares that can be used if it's just a question of having one alternative gateway. Smoothwall is one good alternative. http://www.smoothwall.org (Don't have server functions like the SME, only firewall/gateway.)

[arne]

How is things going, did you find any practical and ok working solutions for ther problem ?