Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

Default Route Forwarding IP?

Hi there.

I have a stacked Catalyst 3750 configuration tat i'd like to enable inter vlan routing on.

I have the following vlans configured and have enabled inter vlan routng on them:

VLAN 192: IP 10.192.0.1/23

VLAN 193: IP 10.193.0.1/23

I have applied this to my switch and i am able to route through to devices between the two vlan's ok.

Devices on my 192 network i add the following route to a windows device: route add 10.193.0.0 mask 255.255.254.0 10.192.0.1

This works ok and i can ping devices on my 193 vlan.

When configuring the Inter vlan routing i am given the option to add a 'Default Route Forwarding IP'... Is this needed and what is it used for?

Also....  I have a site to site VPN configured from my remote office to devices on my 192 vlan. This works fine and i apply the following static route to evices on my 192 vlan for this:

route add 172.16.0.0 mask 255.255.0.0 10.192.0.253      - 10.192.0.253 being my ASA firewall.

Once i have configured the correct NAT rules on my firewall i'm assuming i would apply the following static route to devices on my 193 VLAN?

route add 172.16.0.0 mask 255.255.0.0 10.193.0.1

Thanks,

J.

  • LAN Switching and Routing
2 REPLIES

Default Route Forwarding IP?

Jamie,

The default route forwarding ip is nothing more than your default gateway for the switch. Your hosts will have the ip of the vlan be their default gateway, and for whatever your switch doesn't know about it will send to it's default gateway. Generally, you'll want to default gateway on your switch to point to your egress device (firewall, router, etc.)

It looks like you're doing a lot of static routing though. Is this for this example, or have you been adding routes directly to your workstations? I would just recommend setting the default gateway on your workstations to point to their respective vlans.

On your ASA, your switch will need to have a route to point to the other side:

ip route 172.16.0.0 255.255.0.0 10.192.0.253

And then your ASA, if you're not running ospf, eigrp, or rip between the ASA and switch, will need to have a route to the switch for subnets that the ASA don't see as locally connected:

route inside 10.193.0.0 255.255.254.0 10.192.0.1 (assuming .1 is your switch)

John

HTH, John *** Please rate all useful posts ***
New Member

Re: Default Route Forwarding IP?

Thanks for that update John.

So on my switch i have added the route suggested back to my office network.

ip route 172.16.0.0 255.255.0.0 10.192.0.253

And on my ASA i have added the following:

route inside 10.193.0.0 255.255.254.0 10.192.0.1 ( 10.192.0.1 is my switch IP yes ).

So to clarify... As long as devices on my 10.193.0.0/23 have thier default gateway set to 10.193.0.1  i should be able to route through to this network from 172.16.0.0/16 with adding any static routes?

For devices on my 10.192.0.0/23 range. Currently they require a route adding to route to 10.193.0.0/23

route add 10.193.0.0 mask 255.255.254.0 10.192.0.1

Can this be done on the router so i don't have to manually do this for all devices?

445
Views
0
Helpful
2
Replies
This widget could not be displayed.