Thanks... That was helpful... I'm not sure why I got it into my head that they were alternatives and not complementary.
Also I have some more technical quesitons about Ganglia... Am I correct in that Ganglia only uses multicast, and so to monitor two clusters on different subnets you must have a router that supports multicast. Also how scalable is Ganglia. I understand that Ganglia caches information about every other machine on each node... at least when I telnet to gmond on a machine all the machines information appears. Would this not generate a lot of overhead in a cluster with thousands of nodes? Thank you for your time! Steve On 6/14/05, Dan Rich <[EMAIL PROTECTED]> wrote: > Stephen Cartwright wrote: > > >I am looking at both Ganglia and Nagios... any comments on how they compare? > > > > > You're comparing apples and oranges. > > Nagios is an active system monitor, it's along the lines of HP Openview > or OpenNMS. It doesn't do any graphing, it is focused on service and > host uptime monitoring. > > Ganglia is better used as a data collector and trending tool, along the > lines of cricket, cacti, mrtg, or any other SNMP monitoring tool that > generates graphs based on collected data. > > We run both (in fact, three of the above, Nagios, Cricket, and Ganglia); > as they all give you different views into the system. Nagios is what > pages me in the middle of the night. Cricket is where we go for > long-term trending and data collection for non-Linux boxen (routers, air > handlers, etc.). And Ganglia gives us high precision system > statistics. Most SNMP monitors only run every 5 minutes, whereas > Ganglia gives you statistics much more frequently. > > -- > Dan Rich <[EMAIL PROTECTED]> | http://www.employees.org/~drich/ > | "Step up to red alert!" "Are you sure, sir? > | It means changing the bulb in the sign..." > | - Red Dwarf (BBC) > > > >
