Real Time plugin is not accurate reading

[linux83]

Hello All,
i install real time plug-in and it's working fine, however the reading is not accurate at all.

our internet link is 2Mbps while real time show me there is a spike up to 3.x Mbps.

Cacti version: Version 0.8.7h
Plugin version: it was v4 and upgrade to 0.5 and the same issue


this is life rate:

Internet-Router-1#show int f0/0 | i rate
30 second input rate 2017000 bits/sec, 273 packets/sec
30 second output rate 292000 bits/sec, 220 packets/sec
Internet-Router-1#show int f0/0 | i rate
30 second input rate 1879000 bits/sec, 265 packets/sec
30 second output rate 288000 bits/sec, 216 packets/sec
Internet-Router-1#show int f0/0 | i rate
30 second input rate 1879000 bits/sec, 265 packets/sec
30 second output rate 288000 bits/sec, 216 packets/sec
Internet-Router-1#show int f0/0 | i rate
30 second input rate 1879000 bits/sec, 265 packets/sec
30 second output rate 288000 bits/sec, 216 packets/sec
Internet-Router-1#show int f0/0 | i rate
30 second input rate 1879000 bits/sec, 265 packets/sec
30 second output rate 288000 bits/sec, 216 packets/sec
Internet-Router-1#show int f0/0 | i rate
30 second input rate 1879000 bits/sec, 265 packets/sec
30 second output rate 288000 bits/sec, 216 packets/sec
Internet-Router-1#show int f0/0 | i rate
30 second input rate 1879000 bits/sec, 265 packets/sec
30 second output rate 288000 bits/sec, 216 packets/sec

this is Real time plugin view:

[hol]

Hello All,
i install real time plug-in and it's working fine, however the reading is not accurate at all.

our internet link is 2Mbps while real time show me there is a spike up to 3.x Mbps.

Cacti version: Version 0.8.7h
Plugin version: it was v4 and upgrade to 0.5 and the same issue


this is life rate:

Internet-Router-1#show int f0/0 | i rate
30 second input rate 2017000 bits/sec, 273 packets/sec
30 second output rate 292000 bits/sec, 220 packets/sec
Internet-Router-1#show int f0/0 | i rate
30 second input rate 1879000 bits/sec, 265 packets/sec
30 second output rate 288000 bits/sec, 216 packets/sec
Internet-Router-1#show int f0/0 | i rate
30 second input rate 1879000 bits/sec, 265 packets/sec
30 second output rate 288000 bits/sec, 216 packets/sec
Internet-Router-1#show int f0/0 | i rate
30 second input rate 1879000 bits/sec, 265 packets/sec
30 second output rate 288000 bits/sec, 216 packets/sec
Internet-Router-1#show int f0/0 | i rate
30 second input rate 1879000 bits/sec, 265 packets/sec
30 second output rate 288000 bits/sec, 216 packets/sec
Internet-Router-1#show int f0/0 | i rate
30 second input rate 1879000 bits/sec, 265 packets/sec
30 second output rate 288000 bits/sec, 216 packets/sec
Internet-Router-1#show int f0/0 | i rate
30 second input rate 1879000 bits/sec, 265 packets/sec
30 second output rate 288000 bits/sec, 216 packets/sec

this is Real time plugin view:

You are compering a nearly real-time measurement (5seconds polling) with a 30sec polling. Always, having bigger polling periods, gives bigger normalization to the graphs. Try to compare real-time output by selecting 30 sec polling. It should be more or less the same with the command output. Also, Cisco devices are updating the interface counters in intervals, this is why Cacti is generating spikes.

[linux83]

Hello Hol,
thanks for your respond, even if i set the polling to 30 Second, i get much less than real interface.

link is full 2Mbps while i'm getting 1.3M or 1.4M max.

on real, i'm using this plugin at work (ISP), i figure this issue once we need to failover some links.

i found that link before shutdown carrying around 200M once i fail the link, the second link with 100M should get around 300 +-.

but i found it's jumping to 500M !, or get down to 60-70 then spike up. this when poller at 5 seconds.

while the live interface showing the acceptable utilization.

any idea will be appreciated.