N-central Help

KBA70001: Remote Control Troubleshooting

Knowledge Base Article #: 70001
Applicable Versions: N-central 6.x, 7.x, 8.x, 9.x
Date Created/Updated: April 27, 2011

Common Issue Number 1

Click into Default Settings, everywhere on this page where you see Remote Execution Download Server IP = change it to your public/external IP address <SERVER IP> and check the box beside it to propogate those settings.

After you have changed that for all of those settings (4 changes) click OK at the botttom to propogate the settings out.

Common Issue Number 2

Your DNS server is listed as an internal address. If I do a NSLOOKUP on your <SERVER FQDN> on your primary DNS server, it is probably going to point to an internal IP address. When you make the remote connection to the N-central server, it asks the N-central server to resolve your FQDN <SERVER FQDN>. If it resolves to an internal address, it will not work outside your internal network. If it resolves to a public/external address, it will work for everyone.

Easiest way to fix this is in the Admin Console, click into Network Settings and change your Primary DNS server to your ISPs primary DNS server, or use a public DNS server.

Common Troubleshooting for Blocked Access

From the machine you want to create the remote control connection do the following and from the target machine on your external network you can try the following:

telnet <SERVER IP> 22

If you can telnet to the N-central server on port 22 and the target machine can telnet to the N-central server, then we know that there should be no firewall blocking the connection.

Common Issue Number 3

In the Network Setup, in the Administrator Console, your N-central Server's Hostname is the same as the FQDN. That creates a problem for remote connections through agents and probes which are set to communicate over the FQDN.

Basically what happens is that during the connection, the Agent / Probe will ask the N-central server to resolve the FQDN to an IP, to communicate to. Since your N-central server resolves the hostname to the N-central server's internal IP, the Agent / Probe, being on an external network, is then losing the connection.

That leaves two options to resolve the issue:

  1. Provide a unique hostname for your N-central server, and update your DNS records accordingly
  2. Set the agents and probes to communicate to the N-central Server's IP instead of the FQDN.

To do this, you will need to change the Default Settings in the Administrator Console - change all of the "Endpoint server address" fields to the IP, and check the "Propagate" checkbox.

Bear in mind that option 1 is the preferred method, as option 2 would create a lot of work if your N-central Server's IP changes at any point.