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kamal06 · Joined: 24 Jun 2008 Posts: 11

How does Cacti/weathermap distinguish traffic between several different Servers. For example if I want to display the traffic from host1 to host2 and from host1 to host3. As far as I know the snmp data from "Data Query [SNMP - Interface Statistics]" just gives the complete input/output traffic of the network card. So isn't it for host2 and host3 together?

Howie · Posted: Mon Jun 29, 2009 10:11 am Post subject:

Only if host1 and host2 share a nic...

If you are collecting data from all three servers, you can see what traffic is entering and leaving each server. It's true that you can't tell how much is going to which other host.

To do that you need something like sflow/ipfix/netflow (if your switch/server supports it) or a packet sniffer. If you can do it per-host, some software firewalls (ipfw and ipf on FreeBSD for example) can keep counters too. It's not that simple to set up, and the details will be fairly specific to your network (OS, switch type etc).

It's not really a weathermap problem though - if you can get it into one of the formats you can use with weathermap (text, rrd, etc), then weathermap can use it.