Home lab assistance

[sgrg07]

Hi all,

I am working on setting up a home lab. I have an ISP wireless modem connected to a cisco 2811router. 

I've done a static route from the cisco router to the internet via the modem. I can ping 8.8.8.8 but cant ping anything else. Does this mean that the cisco router is not connected to the internet?

Also is there a need for a route back from the internet/modem to the router? 

Any feedback would be appreciated.

Many thanks 

[Flavio Miranda]

Hi @sgrg07

You need to configure NAT on you router.

Take a look on how to setup NAT on your router and you will be able to access the internet.

-If I helped you somehow, please, rate it as useful.-

[Julio E. Moisa]

Hi

You need a NAT to translate the private networks to the Public IP or to IP provided by the Wireless modem. Imagine your wireless modem provide IP address from the subnet 192.168.1.0/24 and the gateway is 192.168.1.1, you can set up your router like:

PC ----- g0/1 Router g0/0 ----- WIFI Modem. 

interface g0/0

description TO-WIFI-MODEM

ip address 192.168.1.2 255.255.255.0

ip nat outside

no shutdown

interface g0/1

description MY-LOCAL-NETWORK

ip add 10.0.0.1 255.255.255.0

ip nat inside 

no shutdown

ip route 0.0.0.0 0.0.0.0 192.168.1.1 name TO-INTERNET

192.168.1.1 represents the gateway of the network provided by the WIFI Modem but also you can set up the next hop address (i think you already know what IP is because you can ping the public IP 8.8.8.8) 

ip access-list standard MY-NETWORKS

permit 10.0.0.0 0.0.0.255

ip nat inside source list MY-NETWORKS interface g0/0 overload

I have configured a PAT (A type of NAT) to provide translate may private networks to other network who already have Internet access, so my private networks will have access to Internet through that procedure. 

Hope it is useful

:-)

[sgrg07]

Hi Julio, 

I have an #ip nat in in my LAN interface and #ip nat outside on my WAN interface. I have done a NAT overload (PAT)  on the interface facing the wifi modem permiting the LAN network. 

What my problem is that I can only ping the google dns servers and nothing else. 

I also have a switch connected to my LAN interface from where I cant even ping the Modem's ip (192.168.1.1). the default gateway for the switch is the ip of the the router's LAN interface. 

[Flavio Miranda]

Put your config here mate and let us help you.

 Better attach in txt file. 

-If I helped you somehow, please, rate it as useful.-

[Flavio Miranda]

Hi,

You don't have 'ip nat inside' on your LAN.

And you should use "ip nat outside source list ..."

Correct that and try again.

-If I helped you somehow, please, rate it as useful.-

[sgrg07]

Hi , 

thanks for point that out. I have added that

and also shouldn't it not be ip nat source inside .. since we're tranlating LAN addresses in to public ?

[Flavio Miranda]

Put outside and test.

-If I helped you somehow, please, rate it as useful.-

[paul driver]

Hello

---

@sgrg07 wrote:

Hi all,

I am working on setting up a home lab. I have an ISP wireless modem connected to a cisco 2811router. 

I've done a static route from the cisco router to the internet via the modem. I can ping 8.8.8.8 but cant ping anything else. Does this mean that the cisco router is not connected to the internet?

Also is there a need for a route back from the internet/modem to the router? 

---

The router you say can ping google dns, but nothing else, so i am curious to what static route you have applied, as usually the wan facing interface on your rtr that is attaching to the isp modem is dhcp so theory the rtr should obtain a ip address/subnet mask/default gateway via the ISP

Now the usual default static route would be something similar to this ( providing your receiving a dhcp wan address <---- ip route 0.0.0.0 0.0.0.0 <waninterface> dhcp

Now although it is necessary to NAT, In this case it may not be applicable as you DONT state what the modem is doing, it maybe the modem is already performing NAT on your behalf and as you don't mention any non routable subnets for the local area network being configured i would say at this time you dont require any static routes defined on the isp modem pointing back to your router as the connected interface between the rtr and the isp modem would do the trick anyway.

Can you provide the running configuration of the rtr so we can review it and if applicable provide you with suggestions to get you up and running.

res

Paul

[sgrg07]

Hi Paul,

Thanks for you assistance. 

The interface connected to modem obtained ip from the dhcp in modem. 

I have a static route 0.0.0.0 0.0.0.0 192.168.1.1 from the router to the internet. 

I have got PAT on the router for my LAN network. 

My switch on my LAN network cannot ping anything

I will post the config in txt version so you guys can figure out what needs to be done. 

[paul driver]

Hello

Regards just you router config you posted can you try this:

no ip route 0.0.0.0 0.0.0.0 192.168.1.1
ip route 0.0.0.0 0.0.0.0 FastEthernet0/0 dhcp

int FastEthernet0/1
ip nat inside

res
Paul

[sgrg07]

Hi, 

Just done that. 

Still can only ping google DNS

[Flavio Miranda]

Alright.

From your PC or laptop, if you run the command:

nslookup www.google.com

What answer does it brings?

What I mean is, you need NAT but you also need DNS server.

 On you DHCP scope you can pass the DNS server 8.8.8.8 to your machine or you can config it statically.

 Check that and let me know.

-If I helped you somehow, please, rate it as useful.-

[paul driver]

Hello

From your rtr only can you :

ping 73.163.4.161 source fa0/1

This will tell you two things that wan/NAT connectivity is working from your Lan subnet

Then on a client pc statically assign ( as no dhcp server is active for your lan subnet from what you have posted)
Ip address 10.0.0.x
Subnet =255.255.255.0
D/G 10.0.0.1
DNS= 8.8.8.8

Also
no ip nat pool HOME 192.168.1.1 192.168.1.3 netmask 255.255.255.248
no ip nat inside source list HOME_LAN pool HOME overload

ip nat inside source list HOME_LAN interface fa0/0 overload

test again from cleint
ping 73.163.4.161
ping cisco.com

res
Paul