Snmpd update interface counters slowly or something like this

Posted by Korjavin Ivan on Server Fault See other posts from Server Fault or by Korjavin Ivan
Published on 2012-09-18T17:20:59Z Indexed on 2012/09/20 15:40 UTC
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Filed under:

monitoring

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freebsd

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snmp

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zabbix

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net-snmp

I update one my freebsd box to 9-stable (totally new installation) and install net-snmp for monitoring.

uname -r 
9.1-PRERELEASE

pkg_info net-snmp-5.7.1_7 
Information for net-snmp-5.7.1_7:

Comment:
An extendable SNMP implementation
....


cat /var/db/ports/net-snmp/options 
# This file is auto-generated by 'make config'.
# Options for net-snmp-5.7.1_7
_OPTIONS_READ=net-snmp-5.7.1_7
_FILE_COMPLETE_OPTIONS_LIST= IPV6 MFD_REWRITES PERL PERL_EMBEDDED PYTHON DUMMY TKMIB DMALLOC MYSQL AX_SOCKONLY UNPRIVILEGED
OPTIONS_FILE_UNSET+=IPV6
OPTIONS_FILE_UNSET+=MFD_REWRITES
OPTIONS_FILE_SET+=PERL
OPTIONS_FILE_SET+=PERL_EMBEDDED
OPTIONS_FILE_UNSET+=PYTHON
OPTIONS_FILE_SET+=DUMMY
OPTIONS_FILE_UNSET+=TKMIB
OPTIONS_FILE_SET+=DMALLOC
OPTIONS_FILE_UNSET+=MYSQL
OPTIONS_FILE_UNSET+=AX_SOCKONLY
OPTIONS_FILE_UNSET+=UNPRIVILEGED

I have about 500 vlan on this machine, and collect info about interface through snmpd to 2 different software, zabbix and cacti.

And both of them plot the graphs with blank fields.

zabbix cacti

I tryed change polling time in zabbix, from 15, sec to 30,60,90,120,10. And anyway i have blank fields.

snmpd.conf is empty - only a access controls.

This configuration worked fine on freebsd 8.

Where is my fault? How fix this graphs?

UPD: Changing pooling time, switch off one of agent, doesnt help. I look at zabbix log (recieved data from snmpd) and see that: sorry for russian locale, just look at numbers: zabbix data

and thats is not true, as my "iftop" show speed was about 90Mbits, but snmpd return 2Mbits.

I understand that snmpd doesnt return speed, it return just a counter. But how its possible? why 2Mbit/s ?

I tryed recompile snmpd with 64-bit counters, and without it. In both variants this blank fields present.

So i think its my OS (freebsd) doesnt update interface counters well.

I still collect tcpdump for found this request/response. But have problem with that, to much trash.

UPD2: I decrypt tcpdump-ed file, and public this as google doc at gdocfile

Timediff looks strange.. Like zabbix sometimes "forget" do request, and then do twice at row, ehh

UPD3: I parse log from command "while true; do netstat -bin -I vlan4008 >> /var/log/netstat; sleep 300; done" and load as google docs, and add formula for speed : link

Looks like all counters in OS are good. Now i think problem in : 1. zabbix get request twice at row (and what about cacti) 2. snmpd use counter32

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