Believe me, I sympathize. My first attempt to connect to the Internet
failed due to not considering publishing my policy in a routing
registry (e.g., RADB). See http://www.radb.net, or the routing
registry areas at http://www.arin.net and http://www.ripe.net.
One of my concerns with the way that Internet routing is taught is
that most presentations are about the configuration of a router or
two, when it is essential first to understand how the routers fit
into the global routing system. Playing in the global routing system
involves a lot more than BGP announcements. As you have observed, it
involves address assignment, AS number assignment, and registering a
routing policy at the very least. Reverse DNS, swip/rwhois,
filtering, and many other factors will enter into real-world
operations.
It's also often unclear what people are trying to do when they want
anything beyond single-link, default-routed connectivity to an ISP.
Have you ever been to a convention where officious people push you
around with no explanation other than muttering "security?" I'm
afraid I often hear "load-sharing" muttered in the same way with
respect to Internet connectivity. There is no single thing that is
defined as load sharing, and there are different reasons to want or
not want different load sharing options.
In my BGP tutorials at CertificationZone (member area), I've tried to
emphasize "define policy first, then think about configuration."
You'll also see this philosophy in my tutorials at NANOG, and in my
upcoming book (end of the year) on building service provider networks.
The message remains, whenever someone thinks they are ready to
configure BGP on a live router to an ISP, if that is all they think
they need to do to get connected, they are not ready. Since a lot of
this isn't written down, it's very wise to find a knowledgeable ISP
and work with their presales people very closely.
Finding the clueful people can be a crapshoot, I will admit. I can
think of one national carrier with whom I've dealt in different
cities. For the account in Washington DC, which literally did have
Presidential priority, the particular carrier was slow and
inflexible. For a different account with the same provider in
Nashville, the account team couldn't have been more responsive, both
at sales and engineering levels.
>I know that in our case, trying to use BGP for failover between two
>providers, we
>(a) were required to have a /24 <UUnet> ... no problem
>(b) were required to have an AS# ... no
>problem
>(c) PSI *required* us to 'take posssession' of the maintainer object for our
>/24 ... still working on that part
>a. <<very few people appear to have ever heard of RADB ... very
>frustrating>>
>(d) once we finish (c) we *should* be all set .. unless PSInet finds another
>way to delay us.
Unless, of course, PSInet simply goes into bankruptcy. I wish them
well, but the financial press does seem to suggest that the vultures
are getting very close.
>
>I only send this because the "RADB/ Maintainer Object" part has been a
>really painful delay .. but, that should be resolved today :).
>
>
>Thanks!
>TJ
>
> -----Original Message-----
>From: John Neiberger [mailto:[EMAIL PROTECTED]]
>Sent: Thursday, March 29, 2001 17:08
>To: [EMAIL PROTECTED]
>Cc: [EMAIL PROTECTED]
>Subject: Re: BGP over two ISP links
>
>At a minimum you're going to need a single /24, not two. You would
>announce this prefix on both connections. You're also going to need to
>apply for an autonomous system number from ARIN. Details can be found
>at www.arin.net.
>
>I'm wondering what you're really trying to accomplish. If this extra
>link isn't for redundancy, just load sharing, then why not have two
>connections to the same provider? This is FAR easier to implement, does
>not require a public AS number, and does not require using up an entire
>/24 prefix unnecessarily.
>
>Even if the link is for redundancy, you could multihome to different
>POPs of the same provider. Again, this is easier to implement, doesn't
>require the AS number, and doesn't burn up so many addresses. If you
>have a good provider this is an excellent solution.
>
>I'd seriously consider these other options before you make a decision.
>
>Regards,
>John
>
>>>> "Ruihai An" <[EMAIL PROTECTED]> 3/29/01 2:11:17 PM >>>
>Hi, All,
>
>Here is a quick question:
>We are planning to run BGP over two ISP links to provide loading
>balance.
>But we were told that we will run into major problems if we do not have
>full
>class Cs on both ends.
>
>Could somebody make comment on this?
>
>Thanks
>
>Ruihai
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