On Wed, 2007-01-03 at 15:47 +0100, Mogens Kjaer wrote: > > This question is way off topic, sorry. I have googled and googled and have > > not come up with a answer to my question. > > > > I want to query a switch (via SNMP I think) to get a list of systems > > attached to it. I am using Nagios and would like to determine > > switch/router > > dependencies. Trace route will not work because it will not show > > routers/switches for systems on the same sub-net as the system doing the > > trace route and I have seen where it does not return the network based > > switch a system is attached to, just the router. If I could get a list > > systems attached to a router/switch (not a personnel switch, a managed > > switch) I can correlate the information and build dependencies. I have a > > hand-held Fluke network tester than runs Linux that will do this for me > > when > > I type in a hostname, I would rather do it programmaticly because I have > > over 300 systems I need to do. I am open to any method that works that I > > can script so I don't have to do it every time a new system appears. Just > > in case it matters some systems are attached to a V-lan off a managed > > switch > > and I do NOT have admin rights to the routers or switches. > > > > I wrote a C program that uses SNMP for this. > > It queries the switches and hubs for the MAC addresses > seen at each port and the number of bytes in/out. > > Some switches have a MAC to IP table, else I would > ask the ARP table of the router for a table like this. OpenNMS (http://www.opennms.org) does this if you enable it. > The program then prepares a nice top-10 on the > intraweb showing which computers are generating > most traffic, and another table with traffic > at each switch/hub port. Ntop (http://www.ntop.org) will do nice summaries of traffic by hosts/ports/whatever for whatever systems are bridged to the collecting port. -- Les Mikesell lesmikesell@xxxxxxxxx
