How to change defeult gateway

Unanswered Question
Sep 22nd, 2010

Hello and thanks for reading.

I have two Internet connections, and I'd like to use them like this: One of the LAN and a second one for VoIP and wireless visitors.

I have only one Cisco 3560 (192.168.100.254), one firewall that is the default gateway (192.168.100.1) and one cheap wifi router (192.168.100.5). The switch default gateway is 192.168.100.1

I have connected them like this:

LAN Router

|

Firewall

|

3560 switch

|

Wifi router (DHCP on)

I created a VLAN for the VoIP, assigned some ports to that VLAN, and connected the VoIP devices and the wifi router to these ports.

Now when I connect a wifi device, it gets 192.168.100.1 as the gateway and I can't connect to the Internet.

How do I have to fix this?, I want the wifi clients get the wifi router as their gateway and connect to the Internet while keeping them away of the LAN.

Any help would be great,

Jud

I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
Loading.
mrmoothe Wed, 09/22/2010 - 07:42

Hi Jud,

I'm trying to clarify a few things...

In the below topology

LAN Router

|

Firewall

|

3560 switch

|

Wifi router (DHCP on)

I understand that only the 3560 is a cisco device?

Which device of the above have the two internet connections been plugged into?

If it is into different devices, please specify the ports that the internet connections are connected to with each device.

Secondly, what kind of internet connections are there? Are they directly going to the ISP or do you another dialing device like a cable modem in the middle?

-- Manas

JudAster2010 Wed, 09/22/2010 - 08:57

Hi Manas, thanks for answering,

The LAN router is also a Cisco 800.

I have plugged one of the Internet connections to the firewall (its a Zyxel ZyWALL USG) and the wifi router is plugged to one port (in one of the the VoIP VLAN ports) of the 3560 switch

Internet

|

WAN port of the Firewall

|

3560

|

wifi router (connected one of the LAN ports of the router to one port of the 3560)

Both connections (SHDSL and ADSL) are direclty going to the ISP, no modems.

Thanks,

Jud

mrmoothe Wed, 09/22/2010 - 14:20

What is the subnet used by the internal devices behind the LAN router?

Can you ping 192.168.100.1(firewall) from the devices connected wirelessly?

You would need to NAT the traffic coming from the devices that you connect wirelessly for traffic to flow as expected out to the internet.

Do you know which is the natting device here? Is it the firewall or the routers?

JudAster2010 Wed, 09/22/2010 - 14:50

Hi and thanks Manas,

The subnet of the internal lan is 192.168.100.0/24

No, I can't ping the firewall from the devices connected wirelessly, I guess this can be because the wifi router is plugged in a port that is assigned to a different VLAN?

The firewall is doing the NAT for the LAN clients, the wifi router is also doing NAT

Jud

mrmoothe Wed, 09/22/2010 - 18:58

Internet

|

WAN port of the Firewall

|

3560

|

wifi router (connected one of the LAN ports of the router to one port of the 3560)

Hi Jud let me just summarize what we know so far... correct me if I'm wrong of if I've missecd something.

1. The above diagram is the path that the wireless guys should take to go out to the internet.

2. The wireless guys get an ip address form the wifi router with a default gateway of 192.168.100.1

3. 192.168.100.1 is the ip address present on the Firewall

4. The firewall is configured to NAT for the subnet 192.168.100.x

5. We 'cannot' ping 192.168.100.1 from the wireless guys once they are associated with the wireless router.

Please check whether each of the above 5 points is accurate.

If the above are all correct -

1. What ip addresses do the wireless guys get when they associate with the wifi router?

2. So, for the traffic to flow from the wireless guys to the internet we need them to first reach the wireless router, then go through the switch and then over the WAN port of the firewall to the internet.

Could you upload the config of the 3650? I just want to see what vlan the wifi router is in... and how traffic is getting forwarded throught he 3560.

Actions

This Discussion