KBI 311131 Relator Runs Late When High Frequency SLA Rule Is Used As Pre-requisite Rule
Version
Argent Advanced Technology all versions
Date
Friday, 19 Dec 2014
Summary
Argent AT SLA Rule has the option ‘Run Lightweight SLA Checking With Interval Of xxxx Seconds’ to implement High Frequency SLA checking
The Rule is submitted to Monitoring Engine just like other Rules
However, instead of returning immediately after single execution, the High Frequency SLA Rule will be executed multiple times with the interval specified in the Rule
It returns if the target node is found down, or Relator interval is used up
As results, SLA Rule may not return until the full Relator interval is used up
If such a High Frequency SLA Rule is used as pre-requisite Rule in Relator, the pre-requisite checking will take the full Relator interval
It will simply slow Relator by 100%
So, do not use High Frequency SLA Rule as pre-requisite Rule in Relator
Technical Background
SLA Rule with default option works the same as System Down Rule with TCP/IP Ping option
Resolution
Use System Down Rule with TCP/IP Ping option or SLA Rule with default option as pre-requisite Rule in Relator
It can be combined with the option ‘Post Event Only After Rule Is Broken xxx Times’ to do additional double checks