How traps work

You can set traps to inspect the value of MIB variables periodically. Whenever the value of a MIB variable meets the conditions you specify, a trap is sent to the network management stations on the traphost list. The traphost list specifies the network management stations that receive the trap information.

You can set traps on any numeric variable in the MIB. For example, you can set a trap to monitor the fans on your storage system and have the SNMP application on your network management station show a flashing message on your console when a fan has stopped working.

Traps are persistent. After you set a trap, it exists across reboots until you remove it or modify it.

Follow these guidelines when creating traps:

Use the /etc/mib/traps.dat file to find Object Identifiers (OIDs) for objects in the MIB files of your storage system.
Make sure the condition you intend to trap can be generated in your storage system's environment.
Do not set traps on tabular data. It is possible to set traps on row entries in a sequence--for example, an entry in a table. However, if the order in the table is changed by adding or removing rows, you will no longer be trapping the same numeric variables.