User`s manual

MediaPack
SIP User's Manual 322 Document #: LTRT-65408
14.9 SNMP Manager Backward Compatibility
With support for the Multi Manager Trapping feature, the older acSNMPManagerIP MIB
object, synchronized with the first index in the snmpManagers MIB table, is also supported.
This is translated in two features:
 SET/GET to either of the two MIB objects is identical.
i.e., as far as the SET/GET are concerned OID 1.3.6.1.4.1.5003.9.10.1.1.2.7 is
identical to OID 1.3.6.1.4.1.5003.9.10.1.1.2.21.1.1.3.
 When setting ANY IP to the acSNMPManagerIP (this is the older parameter, not the
table parameter), two more parameters are SET to ENABLE. snmpManagerIsUsed.0
and snmpManagerTrapSendingEnable.0 are both set to 1.
14.10 SNMP NAT Traversal
A NAT placed between the gateway and the element manager calls for traversal solutions:
 Trap source port: all traps are sent out from the SNMP port (default 161). A manager
receiving these traps can use the binding information (in the UDP layer) to traverse
the NAT back to the device.
The trap destination address (port and IP) are as configured in the snmpTargetMIB.
 acKeepAliveTrap: this trap is designed to be a constant life signal from the device to
the manager allowing the manager NAT traversal at all times. The
acBoardTrapGlobalsAdditionalInfo1 varbind has the device’s serial number.
The destination port (i.e., the manager port for this trap) can be set to be different than
the port to which all other traps are sent. To do this, use the
acSysSNMPKeepAliveTrapPort object in the acSystem MIB or the ini file parameter
KeepAliveTrapPort.
The trap is instigated in three ways:
• Via an ini file parameter (‘SendKeepAliveTrap = 1’). This ensures that the trap is
continuously sent. The frequency is set via the 9/10 of the
acSysSTUNBindingLifeTime object.
• After the STUN client has discovered a NAT (any NAT).
• If the STUN client cannot contact a STUN server.
Note: The two latter options require the STUN client be enabled
(EnableSTUN). Also, once the acKeepAlive trap is instigated it does
not stop.
 The manager can see the NAT type in the MIB:
audioCodes(5003).acProducts(9).acBoardMibs(10).acSystem(10).acSystemStatus(2).
acSysNetwork(6).acSysNAT(2).acSysNATType(1)
 The manger also has access to the STUN client configuration:
audioCodes(5003).acProducts(9).acBoardMibs(10).acSystem(10).acSystemConfigura
tion(1).acSysNetworkConfig(3).acSysNATTraversal(6).acSysSTUN(21)
 acNATTraversalAlarm: When the NAT is placed in front a device that is identified as
a symmetric NAT, this alarm is raised. It is cleared when a non-symmetric NAT or no
NAT replace the symmetric one.