-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Rainer,
On 1/28/12 8:51 AM, Rainer Jung wrote: > On 26.01.2012 19:32, Christopher Schultz wrote: > >> Now I'm trying to get similar information using a command-line >> tool that is very simple called check_jmx -- it's a plug-in for >> Nagios. It appears that this tool does not support the "attach" >> API and so it looks like I'll have to enable "remote JMX", so >> I've followed the instructions on Tomcat's monitoring page to >> enable remote JMX [3]: > > >> 3. Should I just give up and use the manager app's jmxproxy? I >> don't currently deploy the manager app, and I'd like to avoid >> doing that if possible. But, it may be a slightly cleaner >> solution. >> >> 4. Should I hack the code for check_jmx to use the Attach API >> and try to avoid all of this stupid port business? Getting the >> PID of the Tomcat process shouldn't be hard as long as I use >> CATALINA_PID and get the value from there. > > Note that the naive check_jmx attempt will not scale. Monitoring > JVMs using JMX by starting a new JVM on the polling server for each > poll and each monitored instance will soon killk your monitoring > server. Yeah, we're using check_nrpe to invoke the check_jmx processes on the server that is being monitored, but I expect that we will be monitoring half a dozen JMX variables on several VMs, and that means lots of JVMs being fired up just to connect and ask a simple question. > You either need to use an agent running in the target JVM and > providing access via a simpler non-Java protocol, or you need a > long running Java based gateway, which does the JMX communication > with the target JVMs and gets itself queried with something > simpler. Are you suggesting a long-running process with a persistent connection to the JVM, so that a new JVM for each request can be avoided? Someone has to have done that already, right? > In that sense the Tomcat Manager can act as an agent via its > jmxproxy feature, making JMX data available for each HTTP client > that can parse simle text output. I may consider doing that, though we aren't using the manager app for anything else right now. I'll see if I can use it without allowing access to any other services (like deploy, etc.). > Another a bit more sophisticated approach which can be well > integrated with Nagios is Jmx4Perl as a client in combination with > Jolikia as the agent (all Open Source). I'll check that out. > Of course there are many more options available. I'll document what I find on the wiki. I'm surprised that there's little monitoring information on the Tomcat site. :( - -chris -----BEGIN PGP SIGNATURE----- Version: GnuPG/MacGPG2 v2.0.17 (Darwin) Comment: GPGTools - http://gpgtools.org Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAk8oTw4ACgkQ9CaO5/Lv0PAahQCfQ2NreQ55K10o4DVJQzGRxv9R ZlEAoJ/mc8sUL+q3CDYxJAV1+7XAUib+ =FpZG -----END PGP SIGNATURE----- --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
