Can access server by DNS on the DMZ

[ohareka70]

Hello,

I am trying to access an internal website from the Corporate Network to the DMZ.  The website sits on the DMZ.  I can access it via IP address ie

https://192.168.1.1  but not by DNS name

I also have rules to access it externally from the Internet and i can access it via its DNS name ok ie

https://Thiswebsite.mycompanydomainname.com

Any ideas why DNS would not work interally for it

We have a proxy server internally but it dont know if i need anything setup on it

regards,

Kevin

[chris noon · Accepted solution]

It is likely that your internal host is resolving the address to the public IP address.  If this is the case then you would need rules to go out and back in.

check this by opening a command window (cmd) and typing:

# nslookup [hostname]

does the public IP, private IP or nothing appear?

If the public IP address appears the above is true.  If the private IP address appears then it should be working.  If nothing appers, then nothing is resolving, but this can be fixed in a number of ways.

- Internal DNS server

- Local host entry

- Use the router to resolve DNS 

Let us know how the nslookup goes and we can work on a solution.

[ohareka70]

Chris,

nslookup - It is resolving the address to the public IP address

Externally it works fine and internally it works via IP address ok but not by name

So do i need to create a firewall rule to allow it resolve it internally or do i put a hostname on the server or create an exception on active directory or something like that?

thanks

Kevin

[chris noon · Accepted solution]

you can fix this in one of 2 ways:

1) edit the host file on your local windows machine (http://www.howtogeek.com/howto/27350/beginner-geek-how-to-edit-your-hosts-file/).

2) run a DNS server on your Cisco router and put a local entry on there and then forward all other unknowns to google or your ISP DNS (http://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipaddr_dns/configuration/15-mt/dns-15-mt-book/dns-config-dns.html)