> Do anybody knows if there are any limitations on > number of devices/interfaces mrtg can work with?
The upper limit on number of devices is either limited by cpu or poll-response delay. > As far as I know, mrtg is a single process perl > script. > Therefore, I guess I can run multi-instance of mrtg so > as to take advantge of multi-cpu to catch up the 5-min > polling when there are large number of > devices/interfaces. Others have run multiple instances before, no problem. > However, I am not 100% sure if this works and if there > be any other limitations in large scale deployment. Two issues: a) cycles consumed by polling, and, b) cycles consumed building the graphics from the polled data. The default mrtg configuration is essentially a single- threaded app whose poll completion time is highly dependent on the round-trip poll-response time (including propagation delays, equipment response time, etc). If all devices to be polled responded in exactly 100 milliseconds (WAN), the max would be roughly 3,000 devices. However if all responded in 10 milliseconds (LAN), the max would be about 30,000 devices. (Obviously, lots of assumptions in that basic calculation.) Changing the mrtg config so as to run two independent polling processes would almost double those numbers. So, the bottom line is that throwing a multi-cpu motherboard and/or high speed disk at mrtg isn't going to have much impact if the poll-response times are relatively high. -- Unsubscribe mailto:[EMAIL PROTECTED] Archive http://www.ee.ethz.ch/~slist/mrtg FAQ http://faq.mrtg.org Homepage http://www.mrtg.org WebAdmin http://www.ee.ethz.ch/~slist/lsg2.cgi
