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Probe behind firewall constantly connects/disconnects

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Hi, I just installed a new firewall in front of my core PRTG server. I setup port forward on port 23560 to the server for both TCP & UDP and I can confirm it is open by doing a telnet to port 23560 on the server. Probe log reports connection but then disconnects:


line break30/08/2012 08:03:01 a.m. Login OK: Welcome to PRTG
line break 30/08/2012 08:03:21 a.m. Disconnected from andyslair.dlinkddns.com:23560
line break30/08/2012 08:03:26 a.m. Connected to andyslair.dlinkddns.com:23560<BR>
line break30/08/2012 08:03:27 a.m. Connected<BR>
line break30/08/2012 08:03:27 a.m. Send Login<BR>
line break30/08/2012 08:03:27 a.m. Login OK: Welcome to PRTG
line break30/08/2012 08:03:47 a.m. Disconnected from andyslair.dlinkddns.com:23560
line break30/08/2012 08:03:52 a.m. Connected to andyslair.dlinkddns.com:23560
line break30/08/2012 08:03:53 a.m. Connected
line break30/08/2012 08:03:53 a.m. Send Login
line break30/08/2012 08:03:53 a.m. Login OK: Welcome to PRTG
line break30/08/2012 08:04:13 a.m. Disconnected from andyslair.dlinkddns.com:23560
line break30/08/2012 08:04:18 a.m. Connected to andyslair.dlinkddns.com:23560
line break30/08/2012 08:04:19 a.m. Connected
line break30/08/2012 08:04:19 a.m. Send Login
line break30/08/2012 08:04:19 a.m. Login OK: Welcome to PRTG

On the server, the log also repeated connect/disconnects.

Any idea what is going on or how to fix this? My firewall is a Dlink DFL-210 BTW and I can reach the PRTG web page fine on port 80. The remote probe is also behind a firewall. No port forwards are defined there.

Thanks, AA

disconnects probe repeatedly

Created on Aug 30, 2012 1:19:57 PM by andres11 (80) ●1 ●1



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Hello,

this really does look like a connection issue, something is blocking/interrupting the connection there. Do you have other working Remote Probes?

best regards.

Created on Aug 30, 2012 5:22:57 PM by Torsten Lindner [Paessler Support]



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Yes, I have other remote probes in other locations that work fine. Besides port 23560, are there any other ports I need to open?

Thanks, AA

Created on Aug 30, 2012 9:43:15 PM by andres11 (80) ●1 ●1



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On the Core-Side it's only port 23560 (incoming), on Probe-Side it's an outgoing dynamic port, that can't be set to a specific port.

Created on Aug 31, 2012 9:58:07 AM by Torsten Lindner [Paessler Support]



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