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[SOLVED] Tx & Rx rate via SNMP ?

Posted: Tue May 31, 2016 6:21 pm
by src386
Hello everyone,
I am currently writing a Zabbix template to monitor my RB3011UiAS with SNMP.
I cannot find the oid for Tx rate and Rx rate.
[admin@gw01] /snmp community> /interface print oid
Flags: D - dynamic, X - disabled, R - running, S - slave 
 0  R  name=.1.3.6.1.2.1.2.2.1.2.1 actual-mtu=.1.3.6.1.2.1.2.2.1.4.1 
       mac-address=.1.3.6.1.2.1.2.2.1.6.1 admin-status=.1.3.6.1.2.1.2.2.1.7.1 
       oper-status=.1.3.6.1.2.1.2.2.1.8.1 bytes-in=.1.3.6.1.2.1.31.1.1.1.6.1 
       packets-in=.1.3.6.1.2.1.31.1.1.1.7.1 discards-in=.1.3.6.1.2.1.2.2.1.13.1 
       errors-in=.1.3.6.1.2.1.2.2.1.14.1 bytes-out=.1.3.6.1.2.1.31.1.1.1.10.1 
       packets-out=.1.3.6.1.2.1.31.1.1.1.11.1 discards-out=.1.3.6.1.2.1.2.2.1.19.1 
       errors-out=.1.3.6.1.2.1.2.2.1.20.1
This is weird because in The Dude client, there is an SNMP tab for my device and I can get Tx / Rx rate. Is it calculated from bytes-in and bytes-out ? I cannot afford to do this in Zabbix because it's way too slow and bloated to be reliable.

Does someone have an idea ?
Regards.

Re: Tx & Rx rate via SNMP ?

Posted: Tue May 31, 2016 6:42 pm
by Feklar
TX and RX are bytes-in and bytes-out. What typically happens is the SNMP server polls the device a number of times for these OID's and since it knows the difference in time between these two polls, it uses the difference between the numbers received to calculate the bandwidth for that time slice.

Re: Tx & Rx rate via SNMP ?

Posted: Wed Jun 01, 2016 9:47 am
by src386
TX and RX are bytes-in and bytes-out. What typically happens is the SNMP server polls the device a number of times for these OID's and since it knows the difference in time between these two polls, it uses the difference between the numbers received to calculate the bandwidth for that time slice.
Ok, thanks.

Re: Tx & Rx rate via SNMP ?

Posted: Wed Jun 01, 2016 9:59 am
by pe1chl
This is weird because in The Dude client, there is an SNMP tab for my device and I can get Tx / Rx rate. Is it calculated from bytes-in and bytes-out ? I cannot afford to do this in Zabbix because it's way too slow and bloated to be reliable.
Really? I cannot believe Zabbix is that broken. It is standard practice in monitoring software to calculate rates this way!

Re: Tx & Rx rate via SNMP ?

Posted: Wed Jun 01, 2016 11:21 am
by src386
I just found something interesting here : https://www.zabbix.com/forum/showthread.php?t=27845
There is a builtin calculation for speed in the Zabbix item.
According to documentation :
Store value -> Delta (speed per second) - evaluate value as (value-prev_value)/(time-prev_time)
This is exactly what I needed.