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I can access NTop via IP:3000 though the default login/pass doesn't go anywhere, just a refresh.

And when running "ntopng -v -G /var/run/ -i 1 -s" I get:

[HTTPserver.cpp:350] HTTPS Disabled: missing SSL certificate ? /usr/local/share/ntopng/httpdocs/ssl/ntopng-cert.pem

11:36:50 [HTTPserver.cpp:351] Please read README.SSL if you want to enable SSL

11:36:50 [HTTPserver.cpp:371] ERROR: Unable to start HTTP server (IPv4) on port 3000

I do have a webserver installed and running on the server itself and iptables are off for now. I followed this guide for installation:

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This is a common problem, it happens when the port 3000 isn't free/open.

An easy fix is for you to change the port to a free one, 3050 perhaps by changing the ntopng.conf file in /etc/ntopng/ntopng.conf.

Add the line "-w=3050"(i.e if you choose to use port 3050).

Restart ntopng, all should be well.

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I also had the problem. This is how I solved it:

Using other ports than 3000 didn't work.

I then followed the instructions in the README.SSL and created an SSL certificate. That done, the warnings about the SSL disappeared but

[HTTPserver.cpp:371] ERROR: Unable to start HTTP server (IPv4) on port 3000

remained. After long googling I found this: The symbolic link for the certificate must point to ln -s /usr/lib/ in certain distributions, and openssl-devel must be installed.

After that, ntopng started but I still couldn't log in on the web interface, which was resolved by clearing the browser cache.

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