It depends. If you are running Ntop on a span port < I have no idea on
your setup > / traffic mirror it will track only your local hosts and
all the traffic that they produce.. You just will not see any
connections made coming in since ntop will not track it. I have a large
network here with ~9000 hosts. When I run ntop to track -all- hosts it
will run out of memory  in about 15-30 minutes on a 2GB memory machine..
And soon run out of swap too and ntop will crash.

If I track only local hosts specifying subnets I still get the traffic
they do.. But I do not get any p2p tracking info like I do when I track
foreign hosts as well.

I wish I could do it 100% of the time, ntop gives me great information
tracking foreign hosts. I use it sometimes just if I see a serious spike
and I want to know where and who they are connecting to if even for the
15 min it runs =).


By the way, what do the logs say when it eats up this memory ? This
information is quite usefull sometimes.


-----Original Message-----
From: Juan Puchalski [mailto:[EMAIL PROTECTED] 
Sent: Sunday, March 09, 2003 9:50 PM
To: [EMAIL PROTECTED]
Subject: RE: [Ntop] NTOP eating memory without stopping



Thanks for your quick reply!

>What's your traffic flow - is the a DLS/Cable/dial w/ a few hosts?

I run 2x384 frame relay links, which average a 50% usage on a 24h
period.

>1. Get a real system... Doesn't have to be a P$-3.06g w/ 2GB of ram, 
>but something a little beefier - add memory - it's cheap today ...  
>After the OS and all the other cr*p running, how much is really 
>available to ntop w/o swapping - that's the critical measurement.  Once

>ntop starts to swap, you're dead - walking the tables to compute 
>throughput etc. puts a big load on the system.

Yeah, I can see your point. When NTOP isn't running, there's around 47
megs free in the server. When I run it, it gobbles it up quickly and
starts to swap. The thing is, I'm pretty much cash/hardware strapped. I
live in a south american country going thru an almost-civil-war, and
getting new hardware is next to impossible right now.

I saw textinfo.html, and doesn't include any memory usage info. Altho I
just noticed I never did update to .55! I'm still running .3. Do I gain
anything by upgrading to the latest CVS?

>3. Don't track external hosts (use the flag to turn it off).  People 
>connecting to you can add a big # of hosts you may not think of.

I thought of this, but it brings a small question. The most important
thing I track with NTOP is the network usage by each host. How many megs
has client A downloaded, who was the culprit of the huge upload spike i
just saw in MRTG and that sort of thing. By not tracking external hosts,
does NTOP still capture the entire traffic each of my hosts do, or just
the L-L traffic inside the network?


Juan Puchalski


_______________________________________________
Ntop mailing list
[EMAIL PROTECTED]
http://listgateway.unipi.it/mailman/listinfo/ntop
_______________________________________________
Ntop mailing list
[EMAIL PROTECTED]
http://listgateway.unipi.it/mailman/listinfo/ntop

Reply via email to