SNMP Traps
The traps supported by Prime Access Registrar enable a standard SNMP management station to receive trap messages from an Prime Access Registrar server. These messages contain information indicating whether a server was brought up or down, or that the proxied remote server is down or has come back online.
A trap is a network message of a specific format issued by an SNMP entity on behalf of a network management agent application. A trap is used to provide the management station with an asynchronous notification of an event.
When a trap is generated, a single copy of the trap is transmitted as a trap PDU to each destination contained within a list of trap recipients.
The list of trap recipients is shared by all events and is determined at server initialization time along with other trap configuration information. The list of trap recipients dictates where Prime Access Registrar traps are directed.
The configuration of any other SNMP agent on the host is ignored. By default, all traps are enabled but no trap recipients are defined. By default, no trap is sent until trap recipients are defined.
Traps are configured using the command line interface (CLI). After configuring traps, the configuration information is re initialized when a server reload or restart occurs.
Note
SNMP queries and traps communication can be performed over IPv6.
When you configure traps, you must provide the following information:
- List of trap recipients (community string for each)
- Suppressing traps for any type of message
- Frequency of traps for any type of message
This section contains the following topics:
Supported Traps
The traps supported by Prime Access Registrar enable the Prime Access Registrar server to notify interested management stations of events, failure, or impending failure conditions. Traps are a network message of a specific format issued by an SNMP entity on behalf of a network management agent application. Traps are used to provide the management station with an asynchronous notification of an event.
This section contains the following topics:
carServerStart
carServerStart signifies that the server has started on the host from which this notification was sent. This trap has one object, carNotifStartType, which indicates the start type. A firstStart indicates this is the server process’ first start. reload indicates this server process has an internal reload. This typically occurs after rereading some configuration changes, but reload indicates this server process did not quit during the reload process.
carServerStop
carServerStop signifies that the server has stopped normally on the host from which this notification was sent.
carInputQueueFull
carInputQueueFull indicates that the percentage of use of the packet input queue has reached its high threshold. This trap has two objects:
- carNotifInputQueueHighThreshold—indicates the high limit percentage of input queue usage
- carNotifInputQueueLowThreshold—indicates the low limit percentage of input queue usage
By default, carNotifInputQueueHighThreshold is set to 90% and carNotifInputQueueLowThreshold is set to 60%.
Note
The values for these objects cannot be changed at this time. You will be able to modify them in a future release of Prime Access Registrar.
After this notification has been sent, another notification of this type will not be sent again until the percentage usage of the input queue goes below the low threshold.
If the percentage usage reaches 100%, successive requests might be dropped, and the server might stop responding to client requests until the queue drops down again.
carInputQueueNotVeryFull
carInputQueueNotVeryFull indicates that the percentage usage of the packet input queue has dropped below the low threshold defined in carNotifInputQueueLowThreshold. This trap has two objects:
- carNotifInputQueueHighThreshold—indicates the high limit percentage of input queue usage
- carNotifInputQueueLowThreshold—indicates the low limit percentage of input queue usage
After this type of notification has been sent, it will not be sent again until the percentage usage goes back up above the high threshold defined in carNotifInputQueueHighThreshold.
carOtherAuthServerNotResponding
carOtherAuthServerNotResponding indicates that an authentication server is not responding to a request sent from this server. This trap has three objects:
- radiusAuthServerAddress—indicates the identity of the concerned server
- radiusAuthClientServerPortNumber—indicates the port number of the concerned server
- carAuthServerType—indicates the type of the concerned server
The index of these three objects identifies the entry in radiusAuthServerTable and carAccServerExtTable which maintains the characteristics of the concerned server.
Note
One should not rely solely on carOtherAuthServerNotResponding for server state. Several conditions, including a restart of the Prime Access Registrar server, could result in either multiple carOtherAuthServerNotResponding notifications being sent or in a carOtherAuthServerResponding notification not being sent. NMS can query the carAuthServerRunningState in carAuthServerExtTable for the current running state of this server.
carOtherAuthServerResponding
carOtherAuthServerResponding signifies that an authentication server which had formerly been in a down state is now responding to requests from the Prime Access Registrar server. This trap has three objects:
- radiusAuthServerAddress—indicates the identity of the concerned server
- radiusAuthClientServerPortNumber—indicates the port number of the concerned server
- carAuthServerType—indicates the type of the concerned server
The index of these three objects identifies the entry in radiusAuthServerTable and carAccServerExtTable which maintains the characteristics of the concerned server.
One should not rely on receiving this notification as an indication that all is well with the network. Several conditions, including a restart of the Prime Access Registrar server, could result in either multiple carOtherAuthServerNotResponding notifications being sent or in a carOtherAuthServerResponding notification not being sent. The NMS can query the carAuthServerRunningState in carAuthServerExtTable for the current running state of this server.
carOtherAccServerNotResponding
carOtherAuthServerNotResponding signifies that an accounting server is not responding to the requests sent from this server. This trap has three objects:
- radiusAccServerAddress—indicates the identity of the concerned server
- radiusAccClientServerPortNumber—indicates the port number of the concerned server
- carAcchServerType—indicates the type of the concerned server
The index of these three objects identifies the entry in radiusAuthServerTable and arAccServerExtTable which maintains the characteristics of the concerned server.
One should not solely rely on this for server state. Several conditions, including the restart of the Prime Access Registrar server, could result in either multiple carOtherAccServerNotResponding notifications being sent or in a carOtherAccServerResponding notification not being sent. The NMS can query the carAccServerRunningState in carAccServerExtTable for current running state of this server.
carOtherAccServerResponding
carOtherAccServerResponding signifies that an accounting server that had previously sent a not responding message is now responding to requests from the Prime Access Registrar server. This trap has three objects:
- radiusAccServerAddress—indicates the identity of the concerned server
- radiusAccClientServerPortNumber—indicates the port number of the concerned server
- carAccServerType—indicates the type of the concerned server
The index of these three objects identifies the entry in radiusAuthServerTable and arAccServerExtTable which maintains the characteristics of the concerned server.
One should not rely on the reception of this notification as an indication that all is well with the network. Several conditions, including the restart of the Prime Access Registrar server, could result in either multiple carOtherAccServerNotResponding notifications being sent or in a carOtherAccServerResponding notification not being sent. The NMS can query the carAccServerRunningState in carAccServerExtTable for the current running state of this server.
carAccountingLoggingFailure
carAccountingLoggingFailure signifies that this Prime Access Registrar server cannot record accounting packets locally. This trap has two objects:
- carNotifAcctLogErrorReason—indicates the reason packets cannot be recorded locally
- carNotifAcctLogErrorInterval—indicates how long to wait until another notification of this type might be sent. A value of 0 (zero) indicates no time interval checking, meaning that no new notification can be sent until the error condition is corrected.
carLicenseUsage
carLicenseUsage signifies the percentage of transactions per second(TPS) or session License Usage.
TPS
The TPS trap is generated when the Prime Access Registrar server reaches license usage slabs namely 80%, 90%, 100%, and 110%. These traps are generated only once for every slab during the increasing steady state. Increasing steady state is a state when Prime Access Registrars’ incoming request rate shows 80% of the license usage over a period of 20 minutes. These traps will be regenerated only if a increasing steady state is observed after a decreasing steady state.
Concurrent Session
The concurrent session trap is generated when the Prime Access Registrar server reaches 80%. The incoming traffic slabs defined for trap generation are 80%, 90%, 100%, and 110% of the licensed Concurrent Sessions. These traps are generated once for every slab during the increasing steady state.
carSigtranLicenseUsage
carSigtranLicenseUsageTrap signifies the percentage of SIGTRAN transactions per second (SIGTRAN TPS) or SIGTRAN session License Usage.
carDiameterPeerDown
carDiameterPeerDown signifies that a Diameter peer is down. The identity of the peer is given by cdbpPeerIpAddress.
carDiameterPeerUp
carDiameterPeerUp signifies that a Diameter peer is up. The identity of the peer is given by cdbpPeerIpAddress.
Configuring Traps
The Prime Access Registrar SNMP implementation uses various configuration files to configure its applications.
This section contains the following topics:
SNMP Configuration
A sample configuration file is available in /cisco-ar/ucd-snmp/share/snmp/snmpd.conf. This configuration file is used to configure SNMP query permissions and trap recipients.
Configuring Trap Recipient
The following example shows the default configuration that sets up trap recipients for SNMP versions v1 and v2c.
Note
Most sites use a single NMS, not two as shown below.
# -----------------------------------------------------------------------------
trapsink zubat trapcom 162
trap2sink ponyta trapcom 162
###############################################################################
Note
trapsink is used in SNMP version 1; trap2sink is used in SNMP version 2.
trapcommunity defines the default community string to be used when sending traps. This command must appear prior to trapsink or trap2sink which use this community string.
trapsink and trap2sink are defined as follows:
trapsink hostname community port
trap2sink hostname community port
Community String
A community string is used to authenticate the trap message sender (SNMP agent) to the trap recipient (SNMP management station). A community string is required in the list of trap receivers.