On a Linux system, the Monitoring Framework will not work when IPv6 is enabled. As a result, the instrumentation of your monitored components on this system will not be loaded into the cacao container, and you will not see them in the Monitoring Console.
Solution There are two possible solutions:
Configure the Monitoring Framework to not use the loopback interface:
In the Monitoring Framework configuration directory (default /etc/opt/sun/mfwk/config), make a copy of the sample properties file:
cp mfwk.properties.sample mfwk.properties |
Set the following parameter in the newly copied mfwk.properties file:
mfwk.multicast.disableloopback=true |
Restart the node agent, the master agent, and the Monitoring Console with the procedure To Restart a Node Agent in Sun Java Enterprise System 5 Monitoring Guide.
Or disable IPv6 on Red Hat 3.0 with the following steps:
Find this line if it appears in the /etc/modprobe.conf file:
alias net-pf-10 ipv6 |
Change it or add the following line:
alias net-pf-10 off |
Reboot the system. IPv6 should now be disabled.
On Red Hat 4.0, follow the same procedure using the /etc/modules.conf file.
In the process of disabling a monitored component, it should be undeployed from its node agent, but this sometimes freezes. Specifically, the cacaoadm undeploy command never returns and monitoring is blocked in the entire node agent.
Solution Kill the process and restart the node agent, the master agent, and the Monitoring Console with the procedure To Restart a Node Agent in Sun Java Enterprise System 5 Monitoring Guide.
Components that rely on C libraries to interface with the Monitoring Framework may display more slowly in the Monitoring Console when they run in the Linux operating environment.
Solution None.
Components that rely on C libraries may exhibit slower monitoring performance in the Monitoring Console after other components in the same node agent are redeployed or terminated.
Solution Restart the node's Common Agent Container including the node agent, then restart the master agent and the Monitoring Console with the procedure To Restart a Node Agent in Sun Java Enterprise System 5 Monitoring Guide.
Inter-process communication between components that rely on C libraries and the node agent on the same host is not secure. By default, communication uses the loopback interface, thereby reducing the security risk.
Solution None.
Components that rely on Java libraries to interface with the Monitoring Framework may experience performance issues when accessed through SNMP.
Solution None.
Due to a bug in Solaris 9, packets addressed to an IPv4 address are not delivered to listener on an IPv6 socket. This interrupts the discovery mechanism between node agents and the components to be monitored on that host.
Solution Force the node agent's JVM to listen on IPv4 sockets with the following commands:
cacaoadm stop oldvalue=`cacaoadm get-param java-flags --value` cacaoadm set-param java-flags="${oldvalue} -Djava.net.preferIPv4Stack=true" |
Then restart the node agent, the master agent, and the Monitoring Console with the procedure To Restart a Node Agent in Sun Java Enterprise System 5 Monitoring Guide.
If the time on the node agent and master agent hosts is too far out of sync, adding that node in the Monitoring Console will fail. The error log of the master agent's Monitoring Framework will report a severe error “during JRMP connection establishment.”
Solution Set the time on either host so they are synchronous.
Documentation for a private C API was inadvertently included in the run-time packages. The interfaces it describes are private and subject to change at any time, therefore their use is discouraged.
Solution None.
When many monitoring rules are created in parallel in a node agent on the HP-UX operating system, thread numbers in the Java Virtual Machine (JVM) may exceed kernel parameter limits and cause an OutOfMemory exception.
Solution Download and run the HPjconfig tool, as described in the procedure To Optimize Kernel Parameters for Monitoring Framework on HP-UX in Sun Java Enterprise System 5 Monitoring Guide.