NCPA - '[Errno 104] Connection reset by peer'

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nagiostra
Posts: 31
Joined: Sun Nov 06, 2022 4:17 pm

Re: NCPA - '[Errno 104] Connection reset by peer'

Post by nagiostra »

Did it work as expected at some point and then start giving you this error?
nagiostra
Posts: 31
Joined: Sun Nov 06, 2022 4:17 pm

Re: NCPA - '[Errno 104] Connection reset by peer'

Post by nagiostra »

It looks like a firewall issue. Typically this would be the Windows server saying I'm here, and I'm listening, but I'm not going to let you connect. Can you think of any changes you made on the Windows server in between when it worked and when it didn't?
nagiostra
Posts: 31
Joined: Sun Nov 06, 2022 4:17 pm

Re: NCPA - '[Errno 104] Connection reset by peer'

Post by nagiostra »

It looks like a firewall issue. Typically this would be the Windows server saying I'm here, and I'm listening, but I'm not going to let you connect. Can you think of any changes you made on the Windows server in between when it worked and when it didn't?
nagiostra
Posts: 31
Joined: Sun Nov 06, 2022 4:17 pm

Re: NCPA - '[Errno 104] Connection reset by peer'

Post by nagiostra »

Run these three commands from the command line on your XI host and post the results:
nmap https:ip_of_windows_host:5693
curl -v https:ip_of_windows_host:5693/ -k
telnet ip_of_windows_host 5693
nagiostra
Posts: 31
Joined: Sun Nov 06, 2022 4:17 pm

Re: NCPA - '[Errno 104] Connection reset by peer'

Post by nagiostra »

Actually, the first command should be:
nmap ip_of_windows_host:5693

My bad. Copy/Paste mistake
nagiostra
Posts: 31
Joined: Sun Nov 06, 2022 4:17 pm

Re: NCPA - '[Errno 104] Connection reset by peer'

Post by nagiostra »

Sorry, remove the :5693 from the command. Should be ip_of_windows_host
nagiostra
Posts: 31
Joined: Sun Nov 06, 2022 4:17 pm

Re: NCPA - '[Errno 104] Connection reset by peer'

Post by nagiostra »

And run the curl command just like this and post the results:

curl -v https://192.168.64.49:5693/ -k

and the nmap command like this:

nmap 192.168.64.49:5693
nagiostra
Posts: 31
Joined: Sun Nov 06, 2022 4:17 pm

Re: NCPA - '[Errno 104] Connection reset by peer'

Post by nagiostra »

On the Windows host, The nmap command's output tells us that the ncpa listener service either isn't running, or port 5693 isn't open on the firewall or you have an ssl issue. If the listener service isn't running (check your services app on the windows host) make sure that startup type is automatic and start it. If it's running, then ssl is refusing the connection. In this case, as notepad as administrator edit the file C:\Program Files (x86)\Nagios\NCPA\etc\ncpa.cfg and in the listener configuration section, change loglevel = Warning to loglevel = Debug and restart the listener service in your Services app. The next time you get the error, open C:\Program Files (x86)\Nagios\NCPA\var\log\ncpa_listener.log and post the contents. If the file has become large. just the last 20 or so lines should be sufficient.
nagiostra
Posts: 31
Joined: Sun Nov 06, 2022 4:17 pm

Re: NCPA - '[Errno 104] Connection reset by peer'

Post by nagiostra »

*as notepad in notepad
nagiostra
Posts: 31
Joined: Sun Nov 06, 2022 4:17 pm

Re: NCPA - '[Errno 104] Connection reset by peer'

Post by nagiostra »

It is strange indeed. The fact that it was working and then stopped working and that it's clearly an SSL issue suggests that windows update made a change to SSL. Microsoft will do that to you. Did Update run at any time around the time this behavior started? I'll keep digging.
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