VLAN 2 can not reach the internet.
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12-01-2013 05:47 PM - edited 03-07-2019 04:52 PM
I have two VLANs 2 and 3, VLAN 3 is my user network and VLAN 2 is my server network. The two VLANs can talk, but VLAN 2 can not get out to the internet. What am I doing wrong?
Building configuration...
Current configuration : 2735 bytes
!
! Last configuration change at 02:42:02 UTC Thu Mar 4 1993
!
version 15.0
service config
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname oacSwitch1
!
boot-start-marker
boot-end-marker
!
enable secret 4 *************
enable password *************
!
no aaa new-model
system mtu routing 1500
ip routing
!
!
!
!
!
!
!
!
spanning-tree mode pvst
spanning-tree extend system-id
!
vlan internal allocation policy ascending
!
!
!
!
!
!
interface FastEthernet0
no ip address
no ip route-cache
!
interface GigabitEthernet0/1
switchport access vlan 3
spanning-tree portfast
!
interface GigabitEthernet0/2
switchport access vlan 3
spanning-tree portfast
!
interface GigabitEthernet0/3
switchport access vlan 3
spanning-tree portfast
!
interface GigabitEthernet0/4
switchport access vlan 3
spanning-tree portfast
!
interface GigabitEthernet0/5
switchport access vlan 3
spanning-tree portfast
!
interface GigabitEthernet0/6
switchport access vlan 3
spanning-tree portfast
!
interface GigabitEthernet0/7
switchport access vlan 2
switchport mode access
spanning-tree portfast
!
interface GigabitEthernet0/8
switchport access vlan 2
switchport mode access
spanning-tree portfast
!
interface GigabitEthernet0/9
switchport access vlan 3
spanning-tree portfast
!
interface GigabitEthernet0/10
switchport access vlan 3
spanning-tree portfast
!
interface GigabitEthernet0/11
switchport access vlan 3
spanning-tree portfast
!
interface GigabitEthernet0/12
switchport access vlan 3
spanning-tree portfast
!
interface GigabitEthernet0/13
switchport access vlan 3
spanning-tree portfast
!
interface GigabitEthernet0/14
switchport access vlan 3
spanning-tree portfast
!
interface GigabitEthernet0/15
switchport access vlan 3
spanning-tree portfast
!
interface GigabitEthernet0/16
switchport access vlan 3
spanning-tree portfast
!
interface GigabitEthernet0/17
switchport access vlan 3
!
interface GigabitEthernet0/18
switchport access vlan 3
!
interface GigabitEthernet0/19
switchport access vlan 3
!
interface GigabitEthernet0/20
switchport access vlan 3
!
interface GigabitEthernet0/21
switchport access vlan 2
!
interface GigabitEthernet0/22
switchport access vlan 3
!
interface GigabitEthernet0/23
switchport access vlan 3
!
interface GigabitEthernet0/24
switchport access vlan 3
!
interface Vlan1
no ip address
shutdown
!
interface Vlan2
ip address 10.0.0.1 255.255.0.0
!
interface Vlan3
ip address 192.168.0.2 255.255.255.0
!
ip http server
ip route 0.0.0.0 0.0.0.0 192.168.0.1
!
!
line con 0
line vty 0 4
password *************
login
line vty 5 15
password *************
login
!
end
- Labels:
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LAN Switching

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12-01-2013 07:30 PM
What's doing your natting? The switch has a default route to 192.168.0.1. What device is that, and does it know about the 10.0.0.0/16 subnet?
HTH,
John
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12-01-2013 07:49 PM
It is a comcast bussness gateway (the SMC not the netgear) and I have added the static route for it.
Static Route Table
Name | Destination IP | Subnet Mask | Gateway IP | Active | |
---|---|---|---|---|---|
Servers | 10.0.0.0 | 255.255.0.0 | 192.168.0.2 | Remove |
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12-02-2013 02:34 AM
Hi,
I'm not sure that the gateway will NAT a non directly connected subnet and in this case it won't work without another NAT device between the switch and the gateway
Regards
Alain
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12-02-2013 03:21 AM
would I be able to asing a public IP to it and go out that way?

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12-02-2013 04:08 AM
What Alain is saying is that you have two subnets listed in your switch. The comcast modem may support static routes, but it may only support natting it's primary IP address that's configured on its lan. For example, from your config I assume that vlan 3 is the vlan that the comcast modem is configured as. If you were to change the lan side ip address on the modem to vlan 2, your vlan 2 would be able to get out, but vlan 3 would not. The only way that I can see getting around this is to get a router, or ASA, and put it between your comcast modem and switch. Have the public address passed to the router/ASA and then you can do your natting on that device.
HTH,
John
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12-02-2013 05:31 AM
Hi,
You have to change the ip address 192.168.0.1 to be on a different subnet than VLAN 2 and 3, then for the port connected to your gateway disable switchport (layer 2 port) and enable layer 3 port by adding an ip address to that port.
http://www.cisco.com/en/US/tech/tk389/tk815/technologies_configuration_example09186a008019e74e.shtml
Regards,
Khaled Omar
