I'm in New Orleans and just got my network back up today after
Hurricane Katrina.  The location where my 3640 router formerly
connected to was under water so my ISP re-routed all these circuits to
Atlanta.  Now my 3640 is connected to a Juniper Networks router
instead of a 7206.

After they configured my interface on their router, I could ping that
interface but nothing beyond it.  When I ran a traceroute to my router
from outside , it stopped at the ISP's router.  The ISP network tech
directed me to change my default route from:
ip route 0.0.0.0 0.0.0.0 Ethernet0/0
to:
ip route 0.0.0.0 0.0.0.0 xx.yy.12.1 1

This solved the problem.  Why?
 
--
Bob Simon
remove both "x"s from domain for private replies

On Fri, 04 Nov 2005 19:05:46 -0600, Bob Simon <bsimon@xtnex.net>
wrote:

>I'm in New Orleans and just got my network back up today after
>Hurricane Katrina.  The location where my 3640 router formerly
>connected to was under water so my ISP re-routed all these circuits to
>Atlanta.  Now my 3640 is connected to a Juniper Networks router
>instead of a 7206.
>
>After they configured my interface on their router, I could ping that
>interface but nothing beyond it.  When I ran a traceroute to my router
>from outside , it stopped at the ISP's router.  The ISP network tech
>directed me to change my default route from:
>ip route 0.0.0.0 0.0.0.0 Ethernet0/0
>to:
>ip route 0.0.0.0 0.0.0.0 xx.yy.12.1 1
>
>This solved the problem.  Why?
> 
Sorry, I forgot to mention that I'm not running any routing protocol;
just using static routes.

 
--
Bob Simon
remove both "x"s from domain for private replies

In article <ng0om1dqp1khtm8sfndj475kpb9ktdt5u3@4ax.com>,
 Bob Simon <bsimon@xtnex.net> wrote:

> I'm in New Orleans and just got my network back up today after
> Hurricane Katrina.  The location where my 3640 router formerly
> connected to was under water so my ISP re-routed all these circuits to
> Atlanta.  Now my 3640 is connected to a Juniper Networks router
> instead of a 7206.
> 
> After they configured my interface on their router, I could ping that
> interface but nothing beyond it.  When I ran a traceroute to my router
> from outside , it stopped at the ISP's router.  The ISP network tech
> directed me to change my default route from:
> ip route 0.0.0.0 0.0.0.0 Ethernet0/0
> to:
> ip route 0.0.0.0 0.0.0.0 xx.yy.12.1 1
> 
> This solved the problem.  Why?

Cisco does proxy ARP by default, Juniper doesn't.

-- 
Barry Margolin, barmar@alum.mit.edu
Arlington, MA
*** PLEASE post questions in newsgroups, not directly to me ***

"Barry Margolin" <barmar@alum.mit.edu> wrote in message
news:barmar-CBC9AE.20582904112005@comcast.dca.giganews.com...
> In article <ng0om1dqp1khtm8sfndj475kpb9ktdt5u3@4ax.com>,

> The ISP network tech
> > directed me to change my default route from:
> > ip route 0.0.0.0 0.0.0.0 Ethernet0/0
> > to:
> > ip route 0.0.0.0 0.0.0.0 xx.yy.12.1 1
> >
> > This solved the problem.  Why?
>
> Cisco does proxy ARP by default, Juniper doesn't.

I think this need some more explanation:

When you point your routes to an interface the device will ARP for the
address.
Other devices, such as firewalls, and routers, with Proxy-ARP disabled, will
not reply to such requests.
Hence if you specify the IP instead, your setup will work.

HTH
Martin Bilgrav


>
> -- 
> Barry Margolin, barmar@alum.mit.edu
> Arlington, MA
> *** PLEASE post questions in newsgroups, not directly to me ***