Submit a ticketCall us

Announcing NPM 12.2
With NPM 12.2 you can monitor your Cisco ASA firewalls, to monitor VPN tunnels for basic visibility and troubleshooting tunnels. NPM 12.2 also uses the SolarWinds Orion Installer so you can easily install and upgrade one or more Orion Platform products simultaneously.
See new features and improvements.

Home > Success Center > Network Performance Monitor (NPM) > Availability Statistics value for previous month changes daily

Availability Statistics value for previous month changes daily

Table of contents
Created by Tiarnan Stacke, last modified by MindTouch on Jun 23, 2016

Views: 21 Votes: 1 Revisions: 3

Overview

This article explains why the Last month - Availability field in the Availability Statistics resource found in the Node details view does not provide static values for the previous month.

Environment

  • All NPM versions
  • All SAM versions

Detail

The changing values are caused by the nightly maintenance results. The maintenance summarizes data that is older than seven (7) days into an hourly table and data older than 30 days into a daily table and is displayed from several rows into one, displaying only an average value. 

For example:

Detail table:
2014-07-22 00:10:00 100
2014-07-22 00:00:00 60
2014-07-21 23:50:00 70
2014-07-21 23:40:00 100


Hourly table:
2014-07-20 3:00:00 100
2014-07-20 2:00:00 100
2014-07-20 1:00:00 100
2014-07-20 0:00:00 100


AVG is (100+60+70+100+100+100+100+100)/8 = 91.25


Detail table for next day:
2014-07-22 00:10:00 100
2014-07-22 00:00:00 60


Hourly table for next day:
2014-07-21 23:00:00 85 <-- summarized (70+100)/2

2014-07-20 3:00:00 100
2014-07-20 2:00:00 100
2014-07-20 1:00:00 100
2014-07-20 0:00:00 100


AVG is (100+60+85+100+100+100+100)/7 = ~ 92.142 

 

Note: You may increase the Retention Settings of the Data in Settings > Polling Settings to prevent this. However, this will lead to database growth and cause some performance issues.

 

Last modified
21:47, 22 Jun 2016

Tags

Classifications

Public