On the server hosting PRTG monitoring tool (lets call it SERVER1) , the DNS servers were not set.

On the network I am monitoring, i have COMPUTERNAME1(192.168.1.2) and COMPUTERNAME2(192.168.1.3) which are both connected to Internet via the Cisco router that is being monitored.

On the TopLists of my custom Netflow v9 sensor, i am listing the Destination IP.

In my TopList, the local computers are displayed properly : COMPUTERNAME1(192.168.1.2) COMPUTERNAME2(192.168.1.3)

But the websites being visited are displayed without their DNS names :

[209.191.122.70] [209.191.122.71]

Which is logical since the DNS servers are not setup on the server.

But then I decided to setup thos DNS : 202.106.46.151 and 202.106.195.68

Now, the local computers are displayed like this : SERVER1(192.168.1.2) SERVER1(192.168.1.3)

But the websites visited are now displayed correctly : www.yahoo.com(209.191.122.70) www.yahoo.com(209.191.122.71)

Why can't I see the names of my local computers anymore ?

Thanks for the help

Article Comments

Hello,
as you have provided DNS servers explicit, now these servers are used and therefore your internal computernames cannot be resolved.
If you have only this two machines, the most easy solution would be adding them to the hosts file of the machine to make PRTG resolve them correct.
Best regards


Feb, 2012 - Permalink

Thanks for your answer. Unfortunately, we have about 100 computers, so this solution is not suitable.

Any other solution ?

Thanks


Feb, 2012 - Permalink

Sorry, no. Apart from of course removing the DNS-Server settings again on the PRTG Host.


Feb, 2012 - Permalink

If you configure your internal DNS Servers to perform forwarding of queries they're not authoritative for, they should be able to resolve both external and internal addresses.
This is not related to PRTG's configuration.


Jun, 2015 - Permalink