[j-nsp] Cisco to Juniper Question

[Eric Van Tol]

> -----Original Message-----
> From: juniper-nsp-bounces at puck.nether.net 
> [mailto:juniper-nsp-bounces at puck.nether.net] On Behalf Of 
> Paul Carter - ehosting Limited
> Sent: Thursday, January 17, 2008 6:16 AM
> To: juniper-nsp at puck.nether.net
> ...
> This will allow any devices connected to the relevant 
> switchport/VLAN on
> the catalyst to use the IP's from 192.168.1.1 - 192.168.1.253 with no
> problems. However, I would like to route 192.168.2.0/24 into 
> this VLAN.
> 
> On the Cisco's this is not a problem, I can simply use this line to
> achieve this:
> 
> ip route 192.168.2.0 255.255.255.0 Vlan100
> 
> However, on the Junipers I am unable to do this. Is this 
> possible, if so
> how would I go about configuring this?
> 
> Many Thanks,
> Paul

It's not what you want to hear, but this is never a good idea.  Routing
a network down a broadcast interface such as this should not be done, as
it tends to create a lot unnecessary ARP request traffic on the LAN.
This can lead to memory/CAM exhaustion and high CPU utilization.

What exactly are you trying to accomplish with this setup?  Is there not
a normal next-hop that you can route to?  Or do 192.168.2.0/24 hosts
exist on this VLAN?  If it's the latter, why not just configure a
secondary address on the interface(s):

interface fe-0/0/0 {
    unit 0 {
        family inet {
            address {
                192.168.1.1/24;
                192.168.2.1/24;
            }
        }
    }
}

However, if you really want to route out an interface (and I'm not sure
if J will allow this out a broadcast interface, as I haven't ever
tried), you do:

set routing-options static route 192.168.2.0/24 next-hop fe-0/0/0.0

Hope this helps,
evt