DHCP Clients can't route to the internet

I must miss something silly.

A Domain Controller with DHCP and DNS enabled has two networks.

One network is the external network with access to the internet.
One network is an internet network which assigns IPs via DHCP

Now a client (in this case a linux client) gets the internal IP just fine but cannot route to the internet. It does have access to the DNS and DHCP server just fine, it can even resolve DNS just fine using nslookup but it just cannot route traffic ..

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Comments

KeithC

Is their a gateway assigned from the DHCP server? Have you tried to ping internal ip's and then external ip's?

RobertKaucher

We need a bit more information.
What is the ipaddress of the default gateway?
What is teh defaultgateway (is the server also a router)?
What is the output of ifconfig on the Linux box?
What is the output of route on the Linux box?

Devilsbane

It sounds like you need to install RRAS and configure this server as a router.

That is the simple solution, but installing RRAS on your DC in a production enviornment is a bad idea. If you are just labbing, then go ahead. I have done something similar in my VMware lab, except I have RRAS and DHCP(configured to only give addresses to the internal network) on server1 (with 2 NIC's) and then have DNS/AD installed on Server2.

RobertKaucher

Devilsbane wrote: »

It sounds like you need to install RRAS and configure this server as a router.

That is the simple solution, but installing RRAS on your DC in a production enviornment is a bad idea. If you are just labbing, then go ahead. I have done something similar in my VMware lab, except I have RRAS and DHCP(configured to only give addresses to the internal network) on server1 (with 2 NIC's) and then have DNS/AD installed on Server2.

+1 This is what I thought initially as well and is why I asked for more details about the router. Although I have used configurations like this in production with SBS servers that have ISA intalled, I have mostly used in labs for the 291 and 293 exams.