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Remote probe access denied




I've installed a remote probe on one of our servers. They are separated by VLAN's. It can connect, as the port on the PRTG Server (23560) is open to access from remote server probe. This is what I receive in the log:

13/12/2010 10:44:01 Connected to
13/12/2010 10:44:01 Login NOT OK: Access denied by IP filter!

I've checked the IP filter, it allows all remote probes and should be fine. I don't know why it is doing this. No firewall is on the local server. Are there any other firewall rules that need to be opened other than 23560 to the remote server? Does it require the reverse firewall rule of 23560 as well?

Many thanks

access-denied ip-filter prtg

Created on Dec 13, 2010 11:00:41 AM

Last change on Dec 14, 2010 12:34:19 PM by  Daniel Zobel [Product Manager]

2 Replies



Just checking: did you check the IP filters within the Web GUI (Settings -> Probes) or the ones of the Server Administration tool?

Created on Dec 13, 2010 4:50:26 PM by  Patrick Hutter [Paessler Support] (7,225) 3 3




I found the problem was within the Web GUI as stated and adding the IP of the server under 'Allow IPs'

Created on Dec 16, 2010 12:19:26 PM

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