Latest revision as of 12:52, 11 May 2017

Overview

Mon can be used to monitor system processes and alert when they fail. The Swivel appliance can use MON to watch the Tomcat process, and even extended to other processes.

Prerequisites

Swivel Appliance 2.x with Webmin

Backup the existing Mon Configuration

Before you make any changes, manually backup /etc/mon/mon.cf using WinSCP, see WinSCP How To Guide.

Configuring Mon

Login to Webmin (for more information see Webmin How To Guide, then select System -> MON Service Monitor/Watch Lists and against the required appliance select tomcat5 (10s)

Under Alert, add a new alert named mail.alert from the drop down with the parameter being the email address you want to send to. Alerts can be defined on different events such as when the service stops or starts. Save the setting when complete.

Testing

• Stop the monitored service and verify email messages are sent.

Troubleshooting

At the command line enter monshow --full

Primary Example, mon working with

 monshow --full
 
      server: localhost
        time: Fri Dec 19 12:48:52 2014
       state: scheduler running
 
   GROUP           SERVICE      STATUS      LAST       NEXT       ALERTS SUMMARY
 R DR_IP           tomcat5      -           68s        00:03:51   none
 R Primary_IP      tomcat5      -           6s         3s         none

Standby Example, mon working Primary and Standby

 monshow --full
 
      server: localhost
        time: Fri Dec 19 12:51:38 2014
       state: scheduler running
 
   GROUP           SERVICE      STATUS      LAST       NEXT       ALERTS SUMMARY
 R Standby_IP      tomcat5      -           7s         2s         none
 R Primary_IP      tomcat5      -           12s        17s        none

Primary Example, mon in failed state:

 Primary monshow --full
 
 server: localhost
 time Fri Dec 5 15:55:57 2014
 state: scheduler running
 
   GROUP      SERVICE      STATUS      LAST      NEXT      ALERTS      SUMMARY
 R Primary_IP tomcat5      FAIL        0s        0s        1
 R DR_IP      tomcat5      FAIL        00:03:10  00:001:49 10

Standby Example, mon in failed state:

 Primary monshow --full
 
 server: localhost
 time Fri Dec 5 15:55:47 2014
 state: scheduler running
 
   GROUP      SERVICE      STATUS      LAST      NEXT      ALERTS      SUMMARY
 R Standby_IP tomcat5      FAIL        5s        4s        1
 R Primary_IP tomcat5      FAIL        2s        27s       1

SSL vulnerability updates stop Mon working

This can be resolved by editing the file /usr/local/tomcat/conf/server.xml and changing both instances of 'sslProtocols=' or 'sslProtocol=' to be 'sslEnabledProtocols=', i.e. adding Enabled. Restart Tomcat, check Tomcat is running then use monshow --full as above.