SNMP Usage

Field

Description

time-stamp

The time between the last initialization of the network entity that issued the trap

 

and the generation of the trap.

 

 

variable_bindings

Additional implementation-specific information relating to the trap.

 

 

SNMP Usage

SNMP requests act on a variable-per-variable basis. However, in most cases, you will want to modify multiple variable first, then after all the changes are done, submit the whole configuration and apply all of the changes at the same time. To accomplish this, the following provisions were made:

•SNMP Get requests are served from the actual configuration the device is using

•SNMP Set requests are cached by the SNMP agent and retained until the configuration is committed

•An additional MIB variable is included in the System Configuration group to let the user control the edition operation. The variable name is configEditionControl and its possible values are:

-noAction

-editing

-applyCfgChanges

-discardCfgChanges

Changing a Configuration

To begin a configuration change, you can modify a variable in the System Configuration group. The SNMP agent automatically changes the configEditionControl value to “editing”. A timer starts to give you a period of time to use the SNMP interface for configuration changes. This expires after 30 minutes of no activity. A detailed explanation of this timeout feature is described below.

Another possibility is to manually set the configEditionControl value to “editing” before changing any other variable. The resulting behavior is the same.

Once an edition has started, you can modify as many variables as needed. When all of the changes have been made, set the configEditionControl value to “applyCfgChanges”. This tells the SNMP agent to validate the cached configuration and, if successful, commit it to flash.

Before committing a configuration to flash, it is validated. If correct, it is saved and the device resets. If there is a problem with the validation, the MIB variable “lastSNMPError” contains the error code and the MIB variable “lastSNMPErrorString” contains the corresponding error message. You can obtain these values using SNMP Get requests. The SNMP agent keeps the cached configuration in memory, so you can review and fix the problem, then try to commit again.

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Hypercom Corporation