Chapter 3 The Real-Time Monitoring Configuration Utility
Installing the CFG and CGI Files for Use by MRTG and RRDTool
Cisco SCA BB SNMP Real Time Monitoring User Guide
3-6 OL-12491-01
*/5 * * * * <Full path to the Perl bin directory>\wperl.exe <Full path to
the MRTG bin directory>\mrtg <RTM directory>\mrtg-cfg\<SCE
address>_scabb_mrtg.cfg
(The exact details of working with Cron are outside the scope of this document.)
rtmcmd creates two crontab.txt sample files for Windows and for Linux/Unix setups in the
destination directory. Use these files to configure Cron.
Note that for Unix/Linux systems, the periodic MRTG invocation command must be followed by
an update permission command (chmod) for RRD files providing reading permissions to the web
server. For the command details, see the crontab sample file created by the rtmcmd utility.
Note When using SELinux (which is a standard feature of Redhat Enterprise 4), several extra steps might be
needed to ensure correct operation of the Apache server. A full discussion of this issue is beyond the
scope of this document, but note the following command which would be useful in case SELinux is
activated and the system log indicates that httpd encounters permission problems: chcon -R -h -t
httpd_sys_content_t <RTM directory>
Note that the polling done by MRTG creates a CPU load on both the workstation where MRTG is
running, and on the SCE platform. Therefore, the following is recommend:
• Polling period of once every 5 minutes
• Maximum number of SCE platforms polled by a single workstation (assuming a Win2K
machine, with Pentium 4, 3.2GHz CPU, and 1GB memory) is 10 SCE platforms
The rtmcmd utility is used to create an updated set of MRTG configuration files and report CGI
files when:
• Adding a new SCE device to the RTM setup.
• A change in the Service Configuration applied to some SCE devices should be reflected in the
reports.
To update your RTM directory perform the following steps:
Step 1 Copy the newly created MRTG CFG files from the mrtg-cfg directory in the rtmcmd target
directory to the mrtg-cfg directory within the RTM directory. The RTM directory is the same
location as specified by the rtm_dir property in the user configuration file.
Step 2 Add a Cron task that invokes MRTG periodically (every 5 minutes) on these CFG files, by adding
a task line to the crontab file. This operation is described in detail in Step 2 of the First
Installation (on page 3-5) section.