Using kSar with Red Hat Enterprise (or CentOS) 7

Hi,

I really like using kSar for troubleshooting on Linux, but it doesn't work out-of-the-box with version 7 of Red Hat Enterprise Linux or its derivatives (CentOS, Scientific Linux, etc.).  It just doesn't work with the standard "sar -a" command, so one of my colleague had a bit of free time and found the combination of arguments that makes it work. It looks like there is one of the options that are included in -a was not included in previous versions, and kSar cannot process the additional output.

Here's the command line that works:

sar -bBdqrRSuvwWyp -I SUM -I XALL -m ALL -n ALL -u ALL -P ALL

The 'p' is, however, optional. I add it to have pretty names for disks instead of dev2-0, dev253, etc.

On a side note, if you want to have better results, change the frequency at which the sar cronjob runs (in /etc/cron.d/sysstat, change the '*/10' by just '*'). Also, if you want to see 'waiting for I/O' data with RHEL 7, go in the Options menu, and click "Show CPU usage stacked"

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