Cannot Login into the GUI

If you locked yourself out of the ntopng GUI after a change in the authentication method, you can reset the ntopng login method to the default one (local authentication) with the following command:

# For ntopng 3.7 and above:
redis-cli set ntopng.prefs.local.auth_enabled 1

# For ntopng 3.6 and below:
redis-cli set ntopng.prefs.auth_type local

After restarting ntopng, you should be able to login with the administrator credentials.

If you forgot the administrator password, you can reset it with the following command:

redis-cli del ntopng.user.admin.password

After restarting ntopng, you can login with the default ntopng credentials (admin, admin).


Some browser plugins that perform javascript blocking may interfere with the login. Sometimes adding an exception for ntopng is not enough. Try to disable them before reporting an issue.

How can I monitor the sites visited by an host?

To monitor the web sites visited by an host, make sure it is local (if unsure about what is a local host check page Hosts). Then, you’ll be able to immediately view its visited sites by following the simple instructions available at Sites.

Note that both plain HTTP sites as well as HTTPS sites are monitored!

How do I know who is using most of my bandwidth?

Is your Internet connection slow? Do you think someone in the network is consuming all the available bandwidth? Well, ntopng helps you in understanding this.

First, have a look at the Dashboard and the Dashboard in the Professional Version. You’ll immediately see the top local talkers and the top remote destinations there!

Then, you can click on any of the hosts that have the highest throughput to see what are they doing. Select the Flows page and sort flows according to an ascending order of the “Actual Thpt” to have visibility on the actually traffic the host is currently doing.

How can I associate an hostname to a certain category?

Let’s say you want to want to associate traffic from and to hostname crazynetwork.it to category “Download-FileTransfer-FileSharing” as you know that that particular host is a mirror for the download of ISO images.

Select the “Settings” wheel and click on “Categories”

Edit Categories

The Edit Categories Menu Entry

Then, add hostname crazynetwork.it to category “Download-FileTransfer-FileSharing” by clicking on “Edit Hosts”.

Edit Category Hostnames

The Edit Category Hostnames Page

Finally, save and from that moment on you’ll have the matching traffic opportunely categorized

Flow With a Custom Category

The Flow Details Page of a Flow with a Custom Category

Additional details and examples can be found at Custom Category Hosts.

How can I estimate the disk space required by ntopng?

The following blog post gives accurate estimations of the disk space required by ntopng to store timeseries and flows: https://www.ntop.org/ntopng/ntopng-disk-requirements-for-timeseries-and-flows/