Basically, I have 2 routers, Let's call them Harlingen, and the other will be Pharr.
In Harlingen, there is a large network, with lots of resources, and in Pharr, there are minimal resources.
There is a PPTP connection between the two routers, and I am able to ping IPs of devices in Harlingen from Pharr. However, DNS resolution is not working. I am unable to resolve the IP addresses of devices in Harlingen.
Is there a way to get DNS to pass through the PPTP tunnel? or do I need to switch to L2TP, or OpenVPN?
Or is this a lost cause, and DNS resolution will not work?
Re: Issue with PPTP COnnection
DNS is just packets, like anything else.
If you can pass ICMP packets across the connection you can theoretically pass DNS packets over the same connection. By default this would work, out of the box, so something is making it not work.
Unfortunately it's kind of hard to give more specific advice since your description is extremely vague - all we know is that there are two routers connected via PPTP. Check that your hosts have a route to their DNS server, that the DNS server has a route back to them, that there are no firewalls dropping DNS traffic between the two, that the DNS server allows those stations to resolve names, that there's no errant NAT statements altering the packets in either direction sending them where they shouldn't be going, etc. - the usual stuff. A good first step would be trying to ping the DNS server.
If you can pass ICMP packets across the connection you can theoretically pass DNS packets over the same connection. By default this would work, out of the box, so something is making it not work.
Unfortunately it's kind of hard to give more specific advice since your description is extremely vague - all we know is that there are two routers connected via PPTP. Check that your hosts have a route to their DNS server, that the DNS server has a route back to them, that there are no firewalls dropping DNS traffic between the two, that the DNS server allows those stations to resolve names, that there's no errant NAT statements altering the packets in either direction sending them where they shouldn't be going, etc. - the usual stuff. A good first step would be trying to ping the DNS server.
Re: Issue with PPTP COnnection
Pinging the DNS server works. And if I create an EoIP tunnel between the two routers, I receive an IP address from the router in Harlingen, and am able to resolve hostnames of local devices. one of the devices I am trying to access is station5nc3. so when the EoIP tunnel is up, and I receive an IP from the DHCP server in Harlingen, I am able to ping station5nc3 and it resolves to its IP address. If I disable the EoIP tunnel, and only have a connection via PPTP, I can ping the IP address, but the hostname does not resolve. I have even tried setting the remote DNS server as my only DNS server, and still no results.