SNMP Integer64 Counter64 values processing

[stan.vasiljev]

Hi team,
I have a few questions - 1) If Zabbix receive SNMP Counter64 value and store it with Custom multiplier=8 like Numeric(integer 64bit) as is Item, would we have Integer64 item overflow or error in processing?
2) Or If Zabbix receive SNMP Counter64 value and store it with Custom multiplier=8 like Numeric(float) Delta (speed per second) Item, would we have such errors too?

3) If SNMP Counter64 is reseted (new value is much less than prewious) - How will be processed Delta (speed per second) Item value? It'll be negative or zero, or we would have incorrectly computed delta?

Case Explanation:
I request SNMP Counter64 value of the switch port In/OutOctets, and want to store it like In/OutBits(In/OutOctets*8) or like Bits Per Second (In/OutOctets*8 Delta) value with Numeric (float) type of info.

My SNMP-based switch port speed monitoring:
1. Agent request IF-MIB::ifHCInOctets for each port
2. Zabbix multiply InOctets value by 8, so we have InBits value.
3. Result stored as Delta (speed per second).

My item example:
SNMP OID: IF-MIB::ifHCInOctets
Type of Info: Numeric (float)
Units: bps
Custom multiplier: 8
Store Value: Delta (speed per second)

I don't find any info about Zabbix 64bit values overflow handling or delta (speed per second) values processing, and I hope You can help me!

I know magic word - "Pleeasee"
With thanks, Zabbix user

[Tenzer]

Zabbix does support handling of ifIn/OutOctets values, you just have to configure the item as follows (example of ifInOctets1 from a switch):

Type: SNMPv2 agent
SNMP OID: 1.3.6.1.2.1.2.2.1.10.1
Type of information: Numeric (float)
Units: B
Use multiplier: Do not use
Store value: Delta (speed per second)

[stan.vasiljev]

Thanks for reply.
I prefer to use "bps" format for port speed monitoring, and some of the switch models have this data already in "bps" format. But if they don't?

[stan.vasiljev]

A little remark

ifInOctets and ifOutOctest have Counter32 type, and they are reset values frequently - how zabbix processed these resets?- see the Question#3 of my initial post about this problem!

[stan.vasiljev]

To avoid problem of the Counter32 resets, I decide to use ifHCInOctets/ifHCOutOctets (Counter64 type) in the aggregate with Multiplier=8 and "Delta" store - but I suppose, this schema can cause overflow.

[Alexei]

The overflows (resets to '0') are handled nicely by ZABBIX.

[stan.vasiljev]

Thanks for reply, Alexsei.
I belief this will save my monitoring from troublesome surprises.
By the way, Zabbix Forum support system is pretty good.
I'm happy like elephant.

[Alexei]

You may always test by yourself how ZABBIX handles different situations using a combination of zabbix_sender with an item having type Trapper.

[stan.vasiljev]

Great event

At long last we can find out how to Zabbix server processes the Big Integer64, Counter64 and Delta values. Because of for new 1.6.1 version we have some comments:

* [DEV-275] changed value processing. Multiplier after delta
* [DEV-274] added overflow check for uint64 for incoming values

I think, these are important improvements, they makes server more stable and easy-to-use.

Thanks to all of the Zabbix development participants.