Here are quick steps to install it on CentOS 5.2 box (upgraded from 5.0 release).

Try to install in easy way:

$ yum install ntop

Most probably yum get failed for missing dependencies such as rrdtool package. If this is the case, download and install this package manually:

$ cd /usr/src
$ wget http://dag.wieers.com/rpm/packages/rrdtool/rrdtool-1.2.23-1.el5.rf.i386.rpm
$ rpm -ivh rrdtool-1.2.23-1.el5.rf.i386.rpm --nodeps

I’ve used –nodeps option in rpm command to ignore any dependencies. Yum will take care of that, we just need rrdtool as of now.

now try again with yum, ntop should be installed successfully:

$ yum install ntop

Configure ntop to suit your requirements, such as which network interface should it monitor and on which port (http port) should it display graphical interface.

$ vim /etc/ntop.conf

Save the file and start ntop with specifying the path of conf file:

$ ntop @/etc/ntop.conf

you can also handle it with more easy ‘service ntop start/stop’ commands.

ntop will start collecting network stats and you can view the graphs and further configure its graphical interface: http://localhost:3000/

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