Connecting Lab Network to Internet

[dbronco]

To start, I have read through the following articles but haven't been able to figure out my issue. 

https://community.cisco.com/t5/network-management/connecting-two-networks/m-p/5209326#M160055

and 

https://community.cisco.com/t5/routing/can-t-connect-to-internet-from-pc-through-home-lab/m-p/4957653#M391179

I have a Lab network that is all static IP on the 10.10.10.0/24 network that I'm trying to connect to the internet through my Comcast router, which has a local network of 10.1.10.0/24. 

I'm connected via Ethernet on port GigabitEthernet 1/0/48 on a C9300. 

From my 9300, I can ping the Comcast router and Google (8.8.8.8) but can't access the internet from my PC (10.10.10.20) connected to the 9300 on GigabitEthernet 1/0/23. 

Can someone provide me some guidance or direction please? 

Thank you

[paul driver]

Hello
Host 10.10.10.20 is on a different subnet (vlan 10) than the Comcast address range being supplied 10.1.10 x (vlan1) as such you will need to perfrom NAT for vlan 10 or put the pc host in vlan 1

C9300 ( if nat is supported)
int vlan 1
ip nat outside

int vlan 10
ip nat inside 

access-list 10 permit 10.10.10.0 0.0.0.255
ip nat inside source-list 10 interface vlan 1
no ip route 0.0.0.0 0.0.0.0 10.1.10.1
ip route 0.0.0.0 0.0.0.0 vlan 1 10.1.10.1

[Richard Burts · Accepted solution]

When you ping the Comcast router from the 9300 it uses the source address as vlan 1. And Comcast recognizes and processes that subnet. When you attempt to access outside using devices in vlan 10 it uses that subnet and I am guessing that Comcast does not know about that subnet. So that is your first problem. 

If you solve the issue about Comcast recognizing the subnet for vlan 10 there is another issue. To access the Internet from vlan 10 something needs to do Network Address Translation. I am not clear that the 9300 can do NAT, So you might need to see if you can get the Comcast to to the NAT.

[dbronco]

We just figured this out a few minutes ago. Deleted Vlan10 and set Vlan1 to how that 10 was configured and got everything working. Thank you. 

[Richard Burts]

Thanks for the update. Glad that our suggestions were helpful and that now things are working.