[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [FW-1] Connecting 2 ISP's with Cisco 2611 and a hub
It's a subnet on Ethernet -- it's allowed to have more than two nodes if the subnet mask is big enough. You probably don't want collisions on that subnet, or to be relaying traffic between the ISPs.... That gets you the *connections*. Now you just need to set up the *routing*. Outbound, it's easy enough to fake something like send all Class A traffic to one ISP and all B and C to the other. It's not guaranteed that that will be the best path for any of it, but you can usually let "the cloud" worry about that. Inbound, odds are that you have address space allocated to you by, and advertised to the world by, *one* of your ISPs. So all inbound traffic is going to arrive from that ISP. And if that ISP has a problem, your inbound traffic will STOP, even though you have a working connection to the other ISP. (If you are trying to use address space from both ISPs, especially if you also do NAT, things get more complicated.) The "normal" way to run a multi-homed (multi ISP) site is to get your own AS (autonomous system) number and address space, and talk BGP4 to your ISPs (who, if they're any good, can help you set this up). But I'm not entirely certain whether a 2611 has enough horsepower for that. There are several boxes on the market which use a sort of "reverse NAT" to allow your site to be reached via multiple address spaces allocated by different ISPs. In order to work, these also have to provide your external DNS, and that's a little funky. If your network can really all be behind a single 2611 (ours is dispersed across several geographic sites), these might be cheaper and simpler to install than BGP4 -- and those *might* be the most important criteria to you. David Gillett > -----Original Message----- > From: Mailing list for discussion of Firewall-1 > [mailto:[email protected]]On Behalf Of > Raymond Hoffman > Sent: Thursday, June 13, 2002 8:23 AM > To: [email protected] > Subject: [FW-1] Connecting 2 ISP's with Cisco 2611 and a hub > > > Hi everyone, > > I received the answer from one ISP engineer. He says that a > Cisco 2611 > with two nic's, one internal and other external and a hub > connecting the > two IPS's and the external nic will do the trick. > > Is this correct? I thought the ISP's were to connect directly to the > router but he assured me that this is quite fine. > > Thanks in advance. > > Raymond > -------------------------------------------------------------- > Raymond Hoffman [email protected] > News World Argentina S.A. http://www.tdm.com > "Tiempos del Mundo" - el periódico de las Americas > Bartolomé Mitre 760, Piso 2 > C1036AAN Buenos Aires, Capital Federal > Argentina > Tel: (54-11) 4345-7300 int. 301 Fax: (54-11) 4345-6777 > ================================================= To set vacation, Out Of Office, or away messages, send an email to [email protected] in the BODY of the email add: set fw-1-mailinglist nomail ================================================= To unsubscribe from this mailing list, please see the instructions at http://www.checkpoint.com/services/mailing.html ================================================= If you have any questions on how to change your subscription options, email [email protected] =================================================
|