SNMP Trap Support
You can monitor for unsolicited SNMP trap messages by using the SNMP trap support. These trap messages may contain helpful data for managing a network.
By using the IBM® i SNMP manager, it is possible to deliver SNMP traps to data queues. All traps that are received on a System i® platform can be routed to user-defined data queues as shown in Figure: SNMP Trap Support. Your applications should monitor the data queue to receive trap information.
SNMP Trap Support
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Configuring Trap Support
SNMP trap support uses the exit point QIBM_QZCA_SNMPTRAP and a data queue that you define. To use SNMP trap support, do the following:
- Use the Work with Registration Information (WRKREGINF) command to determine
if the QIBM_QZCA_SNMPTRAP exit point exists on your system (see Figure: Work with Registration
Information (WRKREGINF) Display). If the exit point does not exist, create and
register the exit point by using this command:
CALL PGM(QUSRGPT) PARM('QIBM_QZCA_SNMPTRAP ' 'ZCAT0100' X'00000000' X'00000000')Note: The first parameter must be 20 characters long.
- Define a data queue of 32780 bytes. For example, to define a data queue
that is called MYQUEUE in library QGPL, enter:
CRTDTAQ DTAQ(QGPL/MYQUEUE) MAXLEN(32780)
- Register the exit program and exit program data with the QIBM_QZCA_SNMPTRAP exit point by using the Work with Registration Information (WRKREGINF) command. For example, see Figure: Work with Registration Information (WRKREGINF) Display through Figure: Add Exit Program - Display 2 of 2.
This configuration only registers the data queue name. You may want to add the program name and library that will use this data queue even though this information is not used by the system.
Figure: Work with Registration Information (WRKREGINF) Display
+--------------------------------------------------------------------------------+ | Work with Registration Information | | | | Type options, press Enter. | | 5=Display exit point 8=Work with exit programs | | | | Exit | | Exit Point | | Opt Point Format Registered Text | | QIBM_QTA_TAPE_TMS TMS00200 *YES | | QIBM_QTF_TRANSFER TRAN0100 *YES Original File Transfer Functi | | QIBM_QVP_PRINTERS PRNT0100 *YES Original Virtual Print Server | | QIBM_QZCA_ADDC ZCAA0100 *YES Add Client exit point | | QIBM_QZCA_REFC ZCAF0100 *YES Refresh Client Information ex | | QIBM_QZCA_RMVC ZCAR0100 *YES Remove Client exit point | | 8 QIBM_QZCA_SNMPTRAP ZCAT0100 *YES | | QIBM_QZCA_UPDC ZCAU0100 *YES Update Client Information exi | | QIBM_QZDA_INIT ZDAI0100 *YES Database Server - entry | | QIBM_QZDA_NDB1 ZDAD0100 *YES Database Server - database a | | QIBM_QZDA_NDB1 ZDAD0200 *YES Database Server - database a | | More... | | Command | | ===> | | F3=Exit F4=Prompt F9=Retrieve F12=Cancel | +--------------------------------------------------------------------------------+
Figure: Work with Exit Programs Display is reached using Option 8 from the display shown in the Figure above.
Figure: Work with Exit Programs
Display
+--------------------------------------------------------------------------------+ | Work with Exit Programs | | | | Exit point: QIBM_QZCA_SNMPTRAP Format: ZCAT0100 | | | | Type options, press Enter. | | 1=Add 4=Remove 5=Display 10=Replace | | | | Exit | | Program Exit | | Opt Number Program Library | | 1 TRAPCHECK QGPL | | | | (No exit programs found.) | | | | | | | | | | | | | | | | Command | | ===> | | F3=Exit F4=Prompt F5=Refresh F9=Retrieve F12=Cancel | +--------------------------------------------------------------------------------+
Figure: Add Exit Program is reached using Option 1 from the Figure above and pressing F10 for additional parameters.
Figure: Add Exit Program - Display 1 of
2
+--------------------------------------------------------------------------------+ | Add Exit Program (ADDEXITPGM) | | | | Type choices, press Enter. | | | | Exit point . . . . . . . . . . . > QIBM_QZCA_SNMPTRAP | | Exit point format . . . . . . . > ZCAT0100 Name | | Program number . . . . . . . . . > 1 1-2147483647, *LOW, *HIGH | | Program . . . . . . . . . . . . > TRAPCHECK Name | | Library . . . . . . . . . . . > QGPL Name, *CURLIB | | Text 'description' . . . . . . . Reroute traps | | | | | | Additional Parameters | | | | Replace existing entry . . . . . > *NO *YES, *NO | | Create exit point . . . . . . . *NO *YES, *NO | | | | | | | | | | More... | | F3=Exit F4=Prompt F5=Refresh F12=Cancel F13=How to use this display | | F24=More keys | +--------------------------------------------------------------------------------+
Figure: Add Exit Program - Display 2 of 2
+--------------------------------------------------------------------------------+ | Add Exit Program (ADDEXITPGM) | | | | Type choices, press Enter. | | | | Exit program data: | | Coded character set ID . . . . *NONE Number, *NONE, *JOB | | Length of data . . . . . . . . *CALC 0-2048, *CALC | | Program data . . . . . . . . . QGPL/MYQUEUE | | | | | | | | | | | | | | | | | | | | | | | | | | Bottom | | F3=Exit F4=Prompt F5=Refresh F12=Cancel F13=How to use this display | | F24=More keys | +--------------------------------------------------------------------------------+
Notes:
- The program data field on the Add Exit Program (ADDEXITPGM) display
contains the library name and the data queue name that will be used by the trap
manager. This data must not exceed 21 bytes.
- The exit program and library do not have to exist when they are added to
the exit point.
- The format for the ZCAT0100 trap data queue entry follows. For details
about the SNMP trap, refer to the Internet standard for the trap message
described in RFC 1155 and RFC 1157. The values for the object type field can be
found in IBM i library QSYSINC, file H, member QTOMEAPI.
Offset Type Field Dec Hex 0 0 CHAR(10) Entry type (always *SNMPTRAP) 10 A CHAR(2) Entry ID (currently 01) 12 C BINARY(4) Version (This is the start of the trap header. All displacements are from the start of the trap header.) 16 10 BINARY(4) Length of community name 20 14 BINARY(4) Displacement to community name 24 18 BINARY(4) Length of enterprise object ID 28 1C BINARY(4) Displacement to enterprise object ID 32 20 BINARY(4) Length of agent address 36 24 BINARY(4) Displacement to agent address 40 28 BINARY(4) Generic trap type 44 2C BINARY(4) Specific trap code 48 30 BINARY(4) Time stamp 52 34 BINARY(4) Number of variable bindings 56 38 BINARY(4) Displacement to first variable binding Note: An array of variable bindings follows. These fields repeat for each variable binding BINARY(4) Length of object name BINARY(4) Displacement to object name BINARY(4) Length of value BINARY(4) Displacement to value BINARY(4) Value type (Values for this field can be found in IBM i library QSYSINC, file H, member QTOMEAPI.) Note: All object names and values follow.
CHAR(*) Object names and values for all variable bindings
- The library name and data queue must be specified in uppercase on the exit
point.
- Multiple exit programs are supported on the QIBM_QZCA_SNMPTRAP exit point.
Each exit program must contain only one data queue.
- A maximum of 100 data queues can be defined.
- The data queue names are retrieved from the exit point only when the trap
manager is started. To activate any changes to the data queues, you must end
the trap manager with the End Trap Manager (ENDTRPMGR) command and restart the
trap manager with the Start Trap Manager (STRTRPMGR) command.
- In the preceding scenario, all traps are added to the data queue. If the queue is locked, damaged, destroyed, or named incorrectly, the traps are lost. It is the responsibility of the user application to remove traps from the queue. No messages are sent if the queue is full or traps not removed.