7.6. Troubleshooting
Though all Monitoring-related activities are conducted through the RHN website, Red Hat provides access to some command line diagnostic tools that may help you determine the cause of errors. To use these tools, you must be able to become the
nocpulse user on the RHN Server conducting the monitoring.
First log into the RHN Server as root. Then switch to the
nocpulse user with the following command:
su - nocpulse
You may now use the diagnostic tools described within the rest of this section.
7.6.1. Examining Probes with rhn-catalog
To thoroughly troubleshoot a probe, you must first obtain its probe ID. You may obtain this information by running
rhn-catalog on the RHN Server as the nocpulse user. The output will resemble:
2 ServiceProbe on example1.redhat.com (199.168.36.245): test 23 ServiceProbe on example2.redhat.com (199.168.36.173): rhel2.1 test4 ServiceProbe on example3.redhat.com (199.168.36.174): SSH5 ServiceProbe on example4.redhat.com (199.168.36.175): HTTP
The probe ID is the first number, while the probe name (as entered in the RHN website) is the final entry on the line. In the above example, the
5 probe ID corresponds to the probe named HTTP.
Further, you may pass the
--commandline (-c) and --dump (-d) options along with a probe ID to rhn-catalog to obtain additional details about the probe, like so:
rhn-catalog --commandline --dump 5
The
--commandline option yields the command parameters set for the probe, while --dump retrieves everything else, including alert thresholds and notification intervals and methods.
The command above will result in output similar to:
5 ServiceProbe on example4.redhat.com (199.168.36.175 ):linux:cpu usageRun as: Unix::CPU.pm --critical=90 --sshhost=199.168.36.175--warn=70 --timeout=15 --sshuser=nocpulse--shell=SSHRemoteCommandShell --sshport=4545
Now that you have the ID, you use it with
rhn-rhnprobe to examine the probe's output. Refer to Section 7.6.2, “Viewing the output of rhn-runprobe” for instructions.
