Remote Monitoring & Management Help

Parallel SNMP Queries and set the SNMP Timeout Value

Parallel SNMP Queries

From Agent 8.13 we introduced significant changes to the way in which the SNMP Check queries and retrieves the SNMP GET OID information.

In previous releases each query ran separately but from Agent 8.13 onwards the SNMP engine was rewritten to support parallelism. The use of parallel SNMP GET requests improves efficiency reducing time and resource usage when running multiple SNMP Checks.

Where SNMPv2c is selected the Advanced Monitoring Agent probes the SNMP Agent to determine whether 64-bit counters are supported and if not supported the Advanced Monitoring Agent will default to SNMPv1 and 32-bit counters.

Please note, due to the nature of parallelism in SNMPv1 if one of the calls does not return information, all of the parallel SNMP Checks initiated with this call are reported as failed. This behavior does not occur in SNMPv2c.

This is illustrated in the below example:

Check

A

B

C

Information

Data

Data

Null

SNMPv1 : Checks A, B and C are reported as failed.

SNMPv2c : Checks A and B are reported as passed, with Check C failed

Send an SNMP request per Check

To return to the pre- Agent 8.13 SNMP Check behavior (sending an SNMP request per check rather than in bulk) depends on the version of the Agent running on the device.

Agent 10 onwards

For Windows Agents from 10 onwards it is necessary to amend the settings.ini file in the FmPlugin folder for each device to include a MAXBATCHSIZE entry.

Log on to the target device, navigate to the FmPlugin folder of the Agent installation directory (by default: C:\Program Files (x86)\Advanced Monitoring Agent\FmPlugin) and open the settings.ini file.

Create an [SNMP] section (if one does not already exist) and enter a MAXBATCHSIZE string with a value of 1 (so only one SNMP request is sent per check) then save the settings.ini file.

For example:

[SNMP]
MAXBATCHSIZE=1

The default MAXBATCHSIZE value is 16 and we would suggest entering a maximum of 64.

Pre-Agent 10

For Windows Agents from 8.13 to 9.13.8 it is necessary to amend the settings.ini file in the main Agent directory for each device to include a MAXOIDSPERREQUEST entry.

Log on to the target device, navigate to the Agent installation folder (by default: C:\Program Files (x86)\Advanced Monitoring Agent) and open the settings.ini file.

Create an [SNMP] section (if one does not already exist) and enter a MAXOIDSPERREQUEST string with a value of 1 (so only one SNMP request is sent per check) then save the settings.ini file.

For example:

[SNMP]
MAXOIDSPERREQUEST=1

The MAXOIDSPERREQUEST string supports values up to 64 (the default).

Set SNMP Timeout Value

Not all SNMP queries will return data within the allotted time period resulting in a Check failure due to a timeout condition. To help alleviate this type of issue from Agent 8.15.3 the SNMP timeout can be configured per device.

Agent 10 onwards

Log on to the target device, navigate to the FmPlugin folder of the Agent installation directory (by default: C:\Program Files (x86)\Advanced Monitoring Agent\FmPlugin) and open the settings.ini file.

Create an [SNMP] section (if one does not already exist) and enter a TIMEOUTINSECONDS string with a value of 10 (seconds) then save the settings.ini file.

For example:

[SNMP]
TIMEOUTINSECONDS=10

The TIMEOUTINSECONDS string supports values up to 10 seconds, which defaults to 4 if not defined

Pre-Agent 10

Log on to the target device, navigate to the Agent installation folder (by default: C:\Program Files (x86)\Advanced Monitoring Agent) and open the settings.ini file.

Create an [SNMP] section (if one does not already exist) and enter a TIMEOUT string with a value up to 10 (seconds) then save the settings.ini file.

For example

[SNMP]
TIMEOUT=10

The TIMEOUT string supports values up to 10 seconds, which defaults to 4 if not defined.

What do you want to do?