Re: Multiple internet providers

[Chuck Swiger <cswiger%mac.com@localhost>]

On Jul 26, 2011, at 6:19 AM, Dima Veselov wrote:
> I have a trivial problem, but found very few information on the internet.

This isn't a trivial problem, actually, but OK.  :-)

> I have multiple internet providers, connected to one NetBSD 5.1 box. What is 
> the best practice for serving these? The result I want to have:
> 
> Incoming connections are replied by the destination address
> Outgoing connection is used depending on source address
> 
> As I understand - only Linux have an ability of two default routes. 
> 
> What is the best practice for that? Is there a need of using some daemon?

Do you have an ASN and a routable address block, or are your IPs are being 
delegated to you from your ISP(s)?  If the former, then you ought to look into 
BGP/EGP peering with your upstream providers to provide proper multihomed 
routing.

Perhaps this is a language nitpick, but Linux doesn't provide multiple default 
routes-- there is only one default route for a given routing FIB, but you can 
set up different routing tables per interface and/or use a policy routing 
mechanism like iproute2.  FreeBSD has the equivalent with setfib, but I'm not 
sure whether that is available in NetBSD.  However, you can still implement 
source-based routing using PF and route-to:

  http://www.openbsd.org/faq/pf/pools.html#outgoing

Regards,
-- 
-Chuck