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Remote Network Monitoring (RMON)
SUMMARY This section describes how Junos OS supports the Remote Network Monitoring (RMON) MIB (RFC 2819) that allows a management device to monitor the values of MIB objects, or variables, against configured thresholds. When the value of a variable crosses a threshold, an alarm and its corresponding event are generated. The event can be logged and can generate an SNMP trap.
RMON Overview
An operational support system (OSS) or a fault-monitoring system can be used to automatically monitor events that track many different metrics, including performance, availability, faults, and environmental data. For example, an administrator might want to know when the internal temperature of a chassis has risen above a configured threshold, which might indicate that a chassis fan tray is faulty, the chassis air flow is impeded, or the facility cooling system in the vicinity of the chassis is not operating normally.
The RMON MIB also defines tables that store various statistics for Ethernet interfaces,
including the etherStatsTable
and the
etherHistoryTable
. The etherStatsTable
contains
cumulative real-time statistics for Ethernet interfaces, such as the number of unicast,
multicast, and broadcast packets received on an interface. The
etherHistoryTable
maintains a historical sample of statistics for
Ethernet interfaces. The control of the etherHistoryTable
, including
the interfaces to track and the sampling interval, is defined by the RMON
historyControlTable
.
To enable RMON alarms, you perform the following steps:
Configure SNMP, including trap groups. You configure SNMP at the [
edit snmp
] hierarchy level.Configure rising and falling events in the
eventTable
, including the event types and trap groups. You can also configure events using the CLI at the [edit snmp rmon event
] hierarchy level.Configure alarms in the
alarmTable
, including the variables to monitor, rising and falling thresholds, the sampling types and intervals, and the corresponding events to generate when alarms occur. You can also configure alarms using the CLI at the [edit snmp rmon alarm
] hierarchy level.Extensions to the
alarmTable
are defined in the Juniper Networks enterprise-specific MIB jnxRmon (mib-jnx-rmon.txt).
This topic covers the following sections:
RMON Alarms
An RMON alarm identifies:
-
A specific MIB object that is monitored.
-
The frequency of sampling.
-
The method of sampling.
-
The thresholds against which the monitored values are compared.
An RMON alarm can also identify a specific eventTable
entry to be
triggered when a threshold is crossed.
Configuration and operational values are defined in alarmTable
in
RFC 2819. Additional operational values are defined in Juniper Networks
enterprise-specific extensions to alarmTable
(jnxRmonAlarmTable
).
This topic covers the following sections:
alarmTable
alarmTable
in the RMON MIB allows you to monitor and poll the
following:
-
alarmIndex
—The index value foralarmTable
that identifies a specific entry. -
alarmInterval
—The interval, in seconds, over which data is sampled and compared with the rising and falling thresholds. -
alarmVariable
—The MIB variable that is monitored by the alarm entry. -
alarmSampleType
—The method of sampling the selected variable and calculating the value to be compared against the thresholds. -
alarmValue
—The value of the variable during the last sampling period. This value is compared with the rising and falling thresholds. -
alarmStartupAlarm
—The alarm sent when the entry is first activated. -
alarmRisingThreshold
—The upper threshold for the sampled variable. -
alarmFallingThreshold
—The lower threshold for the sampled variable. -
alarmRisingEventIndex
—TheeventTable
entry used when a rising threshold is crossed. -
alarmFallingEventIndex
—TheeventTable
entry used when a falling threshold is crossed. -
alarmStatus
—Method for adding and removing entries from the table. It can also be used to change the state of an entry to allow modifications.Note:If this object is not set to
valid
, the associated event alarm does not take any action.
jnxRmonAlarmTable
The jnxRmonAlarmTable
is a Juniper Networks enterprise-specific
extension to alarmTable
. It provides additional operational
information and includes the following objects:
-
jnxRmonAlarmGetFailCnt
—The number of times the internalGet
request for the variable monitored by this entry has failed. -
jnxRmonAlarmGetFailTime
—The value ofsysUpTime
when an internalGet
request for the variable monitored by this entry last failed. -
jnxRmonAlarmGetFailReason
—The reason an internalGet
request for the variable monitored by this entry last failed. -
jnxRmonAlarmGetOkTime
—The value ofsysUpTime
when an internalGet
request for the variable monitored by this entry succeeded and the entry left thegetFailure
state. -
jnxRmonAlarmState
—The current state of this RMON alarm entry.
To view the Juniper Networks enterprise-specific extensions to the RMON Events and Alarms and Event MIB, see https://www.juniper.net/documentation/en_US/junos16.1/topics/reference/mibs/mib-jnx-rmon.txt.
RMON Events
An RMON event allows you to log the crossing of thresholds of other MIB objects. It
is defined in eventTable
for the RMON MIB.
This section covers the following topics:
eventTable
eventTable
contains the following objects:
-
eventIndex
—An index that uniquely identifies an entry ineventTable
. Each entry defines one event that is generated when the appropriate conditions occur. -
eventDescription
—A comment describing the event entry. -
eventType
—Type of notification that the probe makes about this event. -
eventCommunity
—Trap group used if an SNMP trap is to be sent. IfeventCommunity
is not configured, a trap is sent to each trap group configured with thermon-alarm
category. -
eventLastTimeSent
—Value ofsysUpTime
when this event entry last generated an event. -
eventOwner
—Any text string specified by the creating management application or the command-line interface (CLI). Typically, it is used to identify a network manager (or application) and can be used for fine access control between participating management applications. -
eventStatus
—Status of this event entry.Note:If this object is not set to
valid
, no action is taken by the associated event entry. When this object is set tovalid
, all previous log entries associated with this entry (if any) are deleted.
Alarm Thresholds and Events
By setting a rising and a falling threshold for a monitored variable, you can be alerted whenever the value of the variable falls outside the allowable operational range (see Figure 1).
Events are only generated when the alarm threshold is first crossed in any one direction rather than after each sample interval. For example, if a rising threshold alarm, along with its corresponding event, is raised, no more threshold crossing events occur until a corresponding falling alarm occurs. This considerably reduces the quantity of events that are produced by the system, making it easier for operations staff to react when events do occur.
Before you configure remote monitoring, you should identify what variables need to be monitored and their allowable operational range. This requires some period of baselining to determine the allowable operational ranges. An initial baseline period of at least 3 months is not unusual when you first identify the operational ranges and define thresholds, but baseline monitoring should continue over the life span of each monitored variable.
See Also
RMON Alarms and Events Configuration
Junos OS supports monitoring routers from remote devices. These values are measured against thresholds and trigger events when the thresholds are crossed. You configure remote monitoring (RMON) alarm and event entries to monitor the value of a MIB object.
To configure RMON alarm and event entries, you include
statements at the [edit snmp]
hierarchy level of the
configuration:
[edit snmp] rmon { alarm index { description text-description; falling-event-index index; falling-threshold integer; falling-threshold-interval seconds; interval seconds; rising-event-index index; rising-threshold integer; request-type (get-next-request | get-request | walk-request); sample-type (absolute-value | delta-value); startup-alarm (falling-alarm | rising-alarm | rising-or-falling-alarm); syslog-subtag syslog-subtag; variable oid-variable; } event index { community community-name; description description; type type; } }
Configure RMON Alarms and Events
The Junos OS supports the Remote Network Monitoring (RMON) MIB (RFC 2819). This allows a management device to monitor the values of MIB objects, or variables, against configured thresholds. When the value of a variable crosses a threshold, an alarm and its corresponding event are generated. The event can be logged and can generate an SNMP trap.
To configure RMON alarms and events using the CLI, perform these tasks:
Configure SNMP
To configure SNMP:
Configure an Event
To configure an event:
Configure an Alarm
To configure an alarm:
Monitor RMON MIB Tables
Purpose
Monitor remote monitoring (RMON) alarm, event, and log tables.
Action
To display the RMON tables:
user@switch> show snmp rmon Alarm Index Variable description Value State 5 monitor jnxOperatingCPU.9.1.0.0 5 falling threshold Event Index Type Last Event 1 log and trap 2010-07-10 11:34:17 PDT Event Index: 1 Description: Event 1 triggered by Alarm 5, rising threshold (90) crossed, (variable: jnxOperatingCPU.9.1.0.0, value: 100) Time: 2010-07-10 11:34:07 PDT Description: Event 1 triggered by Alarm 5, falling threshold (75) crossed, (variable: jnxOperatingCPU.9.1.0.0, value: 5) Time: 2010-07-10 11:34:17 PDT
Meaning
The display shows that an alarm has been defined to monitor jnxRmon MIB object jnxOperatingCPU, which represents the CPU utilization of the Routing Engine. The alarm is configured to generate an event that sends an SNMP trap and adds an entry to the logTable in the RMON MIB. The log table shows that two occurrences of the event have been generated—one for rising above a threshold of 90 percent, and one for falling below a threshold of 75 percent.
See Also
RMON MIB Event, Alarm, Log, and History Control Tables
Table 1 provides
each field in the RMON eventTable, the description of the field, and
the corresponding Junos OS statement that you can use to configure
the field. The Junos OS statements reside at the [edit snmp
rmon
] hierarchy level.
Field |
Description |
Statement [edit snmp rmon] |
---|---|---|
eventDescription |
Text description of this event. |
|
eventType |
Type of event (for example, log, trap, or log and trap). |
|
eventCommunity |
Trap group to which to send this event, as defined in the Junos OS configuration. (This is not the same as the SNMP community.) |
|
eventOwner |
Entity (for example, manager) that created this event. |
— |
eventStatus |
Status of this row (for example, valid, invalid, or createRequest). |
— |
Table 2 provides each
field in the RMON alarmTable, the description of the field, and the
corresponding Junos OS statement that you can use to configure the
field. The Junos OS statements reside at the [edit snmp rmon
] hierarchy level.
Field |
Description |
Statement [edit snmp rmon] |
---|---|---|
alarmStatus |
Status of this row (for example, valid, invalid, or createRequest) |
— |
alarmInterval |
Sampling period (in seconds) of the monitored variable |
|
alarmVariable |
Object identifier (OID) and instance of the variable to be monitored |
— |
alarmValue |
Actual value of the sampled variable |
— |
alarmSampleType |
Sample type (absolute or delta changes) |
|
alarmStartupAlarm |
Initial alarm (rising, falling, or either) |
|
alarmRisingThreshold |
Rising threshold against which to compare the value |
|
alarmFallingThreshold |
Falling threshold against which to compare the value |
|
alarmRisingEventIndex |
Index (row) of the rising event in the event table |
|
alarmFallingEventIndex |
Index (row) of the falling event in the event table |
|
Table 3 provides each field in the jnxRmon jnxRmonAlarmTable, which is an extension to the RMON alarmTable. You can troubleshoot the RMON agent, rmopd, that runs on a switch by inspecting the contents of the jnxRmonAlarmTable object.
Field |
Description |
---|---|
jnxRmonAlarmGetFailCnt |
Number of times the internal |
jnxRmonAlarmGetFailTime |
Value of the sysUpTime object when the last failure occurred |
jnxRmonAlarmGetFailReason |
Reason why the |
jnxRmonAlarmGetOkTime |
Value of the sysUpTime object when the variable moved out of failure state |
jnxRmonAlarmState |
Status of this alarm entry |
Table 4 provides
each field in the RMON historyControlTable, the description of the
field, and the corresponding Junos OS statement that you can use to
configure the field. The Junos OS statements reside at the [edit
snmp rmon history
] hierarchy level. The historyControlTable
controls the RMON etherHistoryTable.
Field |
Description |
Statement [edit snmp rmon history] |
---|---|---|
historyControlDataSource |
Identifies the source of the data for which historical data was collected. |
|
historyControlBucketsRequested |
Requested number of discrete time intervals over which data is to be saved. |
|
historyControlBucketsGranted |
Number of discrete sampling intervals over which data is to be saved. |
— |
historyControlInterval |
Interval, in seconds, over which the data is sampled for each bucket. |
|
historyControlOwner |
Entity that configured this entry. |
|
historyControlStatus |
Status of this entry. |
— |
Minimum RMON Alarm and Event Entry Configuration
To enable RMON on the router, you must configure an alarm
entry and an event entry. To do this, include the following statements
at the [edit snmp rmon]
hierarchy level:
[edit snmp rmon] alarm index { rising-event-index index; rising-threshold integer; sample-type type; variable oid-variable; } event index;
Configure an RMON Alarm Entry and Its Attributes
An alarm entry monitors the value of a MIB variable. You can configure how often the value is sampled, the type of sampling to perform, and what event to trigger if a threshold is crossed.
This section discusses the following topics:
- Configure the Alarm Entry
- Configure the Description
- Configure the Falling Event Index or Rising Event Index
- Configure the Falling Threshold or Rising Threshold
- Configure the Interval
- Configure the Falling Threshold Interval
- Configure the Request Type
- Configure the Sample Type
- Configure the Startup Alarm
- Configure the System Log Tag
- Configure the Variable
Configure the Alarm Entry
An alarm entry monitors the value of a MIB variable. The rising-event-index
, rising-threshold
, sample-type
, and variable
statements are mandatory. All other statements
are optional.
To configure the alarm entry, include the alarm
statement and specify an index at the [edit snmp rmon]
hierarchy level:
[edit snmp rmon] alarm index { description description; falling-event-index index; falling-threshold integer; falling-threshold-interval seconds; interval seconds; rising-event-index index; rising-threshold integer; sample-type (absolute-value | delta-value); startup-alarm (falling-alarm | rising alarm | rising-or-falling-alarm); variable oid-variable; }
index
is an integer that identifies
an alarm or event entry.
Configure the Description
The description is a text string that identifies the alarm entry.
To configure the description, include the description
statement and a description of the alarm entry at the [edit
snmp rmon alarm index]
hierarchy level:
[edit snmp rmon alarm index] description description;
Configure the Falling Event Index or Rising Event Index
The falling event index identifies the event entry that is triggered when a falling threshold is crossed. The rising event index identifies the event entry that is triggered when a rising threshold is crossed.
To configure the falling event index or rising event
index, include the falling-event-index
or rising-event-index
statement and specify an index at the [edit snmp rmon alarm index]
hierarchy level:
[edit snmp rmon alarm index] falling-event-index index; rising-event-index index;
index
can be from 0 through
65,535. The default for both the falling and rising event index is
0.
Configure the Falling Threshold or Rising Threshold
The falling threshold is the lower threshold for the monitored
variable. When the current sampled value is less than or equal to
this threshold, and the value at the last sampling interval is greater
than this threshold, a single event is generated. A single event is
also generated if the first sample after this entry becomes valid
is less than or equal to this threshold, and the associated startup
alarm is equal to falling-alarm
or rising-or-falling-alarm
. After a falling event is generated, another falling event cannot
be generated until the sampled value rises above this threshold and
reaches the rising threshold. You must specify the falling threshold
as an integer. Its default is 20 percent less than the rising threshold.
By default, the rising threshold is 0. The rising threshold
is the upper threshold for the monitored variable. When the current
sampled value is greater than or equal to this threshold, and the
value at the last sampling interval is less than this threshold, a
single event is generated. A single event is also generated if the
first sample after this entry becomes valid is greater than or equal
to this threshold, and the associated startup-alarm
is
equal to rising-alarm
or rising-or-falling-alarm
. After a rising event is generated, another rising event cannot
be generated until the sampled value falls below this threshold and
reaches the falling threshold. You must specify the rising threshold
as an integer.
To configure the falling threshold or rising threshold,
include the falling-threshold
or rising-threshold
statement at the [edit snmp rmon alarm index]
hierarchy level:
[edit snmp rmon alarm index] falling-threshold integer; rising-threshold integer;
integer
can be a value from
-2,147,483,647 through 2,147,483,647.
Configure the Interval
The interval represents the period of time, in seconds, over which the monitored variable is sampled and compared with the rising and falling thresholds.
To configure the interval, include the interval
statement and specify the number of seconds at the [edit snmp
rmon alarm index]
hierarchy level:
[edit snmp rmon alarm index] interval seconds;
seconds
can be a value from
1 through 2,147,483,647. The default is 60 seconds.
Configure the Falling Threshold Interval
The falling threshold interval represents the interval between samples when the rising threshold is crossed. Once the alarm crosses the falling threshold, the regular sampling interval is used.
You cannot configure the falling threshold interval for
alarms that have the request type set to walk-request
.
To configure the falling threshold interval, include
the falling-threshold interval
statement at the [edit
snmp rmon alarm index]
hierarchy level
and specify the number of seconds:
[edit snmp rmon alarm index] falling-threshold-interval seconds;
seconds
can be a value from
1 through 2,147,483,647. The default is 60 seconds.
Configure the Request Type
By default an RMON alarm can monitor only one object instance
(as specified in the configuration). You can configure a request-type
statement to extend the scope of the RMON alarm to include all object
instances belonging to a MIB branch or to include the next object
instance after the instance specified in the configuration.
To configure the request type, include the request-type
statement at the [edit snmp rmon alarm index]
hierarchy level and specify get-next-request
, get-request
, or walk-request
:
[edit snmp rmon alarm index] request-type (get-next-request | get-request | walk-request);
walk
extends the RMON alarm configuration to all
object instances belonging to a MIB branch. next
extends
the RMON alarm configuration to include the next object instance after
the instance specified in the configuration.
Configure the Sample Type
The sample type identifies the method of sampling the selected
variable and calculating the value to be compared against the thresholds.
If the value of this object is absolute-value
, the value
of the selected variable is compared directly with the thresholds
at the end of the sampling interval. If the value of this object is delta-value
, the value of the selected variable at the last
sample is subtracted from the current value, and the difference is
compared with the thresholds.
To configure the sample type, include the sample-type
statement and specify the type of sample at the [edit snmp
rmon alarm index]
hierarchy level:
[edit snmp rmon alarm index] sample-type (absolute-value | delta-value);
absolute-value
—Actual value of the selected variable is compared against the thresholds.delta-value
—Difference between samples of the selected variable is compared against the thresholds.
Configure the Startup Alarm
The startup alarm identifies the type of alarm that can be sent
when this entry is first activated. You can specify it as falling-alarm
, rising-alarm
, or rising-or-falling-alarm
.
To configure the startup alarm, include the startup-alarm
statement and specify the type of alarm at the [edit snmp rmon
alarm index]
hierarchy level:
[edit snmp rmon alarm index] startup-alarm (falling-alarm | rising-alarm | rising-or-falling-alarm);
falling-alarm
—Generated if the first sample after the alarm entry becomes active is less than or equal to the falling threshold.rising-alarm
—Generated if the first sample after the alarm entry becomes active is greater than or equal to the rising threshold.rising-or-falling-alarm
—Generated if the first sample after the alarm entry becomes active satisfies either of the corresponding thresholds.
The default is rising-or-falling-alarm
.
Configure the System Log Tag
The syslog-subtag
statement specifies the tag to
be added to the system log message. You can specify a string of not
more than 80 uppercase characters as the system log tag.
To configure the system log tag, include the syslog-subtag
statement at the [edit snmp rmon alarm index]
hierarchy level:
[edit snmp rmon alarm index] syslog-subtag syslog-subtag;
Configure the Variable
The variable identifies the MIB object that is being monitored.
To configure the variable, include the variable
statement and specify the object identifier or object name at the [edit snmp rmon alarm index]
hierarchy
level:
[edit snmp rmon alarm index] variable oid-variable;
oid-variable
is a dotted decimal
(for example, 1.3.6.1.2.1.2.1.2.2.1.10.1
) or MIB object
name (for example, ifInOctets.1
).
Configure an RMON Event Entry and Its Attributes
An event entry generates a notification for an alarm
entry when its rising or falling threshold is crossed. You can configure
the type of notification that is generated. To configure the event
entry, include the event
statement at the [edit snmp
rmon]
hierarchy level. All statements except the event
statement are optional.
[edit snmp rmon] event index { community community-name; description description; type type; }
index
identifies an entry event.
community-name
is the trap group
that is used when generating a trap. If that trap group has the rmon-alarm
trap category configured, a trap is sent to all
the targets configured for that trap group. The community string in
the trap matches the name of the trap group. If nothing is configured,
all the trap groups are examined, and traps are sent using each group
with the rmon-alarm
category set.
description
is a text string
that identifies the entry.
The type
variable of an event
entry specifies where the event is to be logged. You can specify the
type as one of the following:
log
—Adds the event entry to thelogTable
.log-and-trap
—Sends an SNMP trap and creates a log entry.none
—Sends no notification.snmptrap
—Sends an SNMP trap.
The default for the event entry type is log-and-trap
.
Example: Configure an RMON Alarm and Event Entry
Configure an RMON alarm and event entry:
[edit snmp] rmon { alarm 100 { description “input traffic on fxp0”; falling-event-index 100; falling-threshold 10000; interval 60; rising-event-index 100; rising-threshold 100000; sample-type delta-value; startup-alarm rising-or-falling-alarm; variable ifInOctets.1; } event 100 { community bedrock; description” emergency events”; type log-and-trap; } }
Use alarmTable to Monitor MIB Objects
To use alarmTable to monitor a MIB object, perform the following tasks:
- Create an Alarm Entry
- Configure the Alarm MIB Objects
- Activate a New Row in alarmTable
- Modify an Active Row in alarmTable
- Deactivate a Row in alarmTable
Create an Alarm Entry
To create an alarm entry, first create a new row in alarmTable using the alarmStatus object. For example, create alarm #1 using the UCD command-line utilities:
snmpset -Os -v2c router community alarmStatus.1 i createRequest
Configure the Alarm MIB Objects
Once you have created the new row in alarmTable, configure the following Alarm MIB objects:
Other than alarmStatus, you cannot modify any of the objects
in the entry if the associated alarmStatus object is set to valid
.
- alarmInterval
- alarmVariable
- alarmSampleType
- alarmValue
- alarmStartupAlarm
- alarmRisingThreshold
- alarmFallingThreshold
- alarmOwner
- alarmRisingEventIndex
- alarmFallingEventIndex
alarmInterval
The interval, in seconds, over which data is sampled and compared
with the rising and falling thresholds. For example, to set alarmInterval
for alarm #1 to 30 seconds, use the following
SNMP Set
request:
snmpset -Os -v2c router community alarmInterval.1 i 30
alarmVariable
The object identifier of the variable to be sampled. During
a Set
request, if the supplied variable name is not available
in the selected MIB view, a badValue error is returned. If at any
time the variable name of an established alarmEntry is no longer available
in the selected MIB view, the probe changes the status of alarmVariable
to invalid. For example, to identify ifInOctets.61 as the variable
to be monitored, use the following SNMP Set
request:
snmpset -Os -v2c router community alarmVariable.1 o .1.3.6.1.2.1.2.2.1.10.61
alarmSampleType
The method of sampling the selected variable and calculating
the value to be compared against the thresholds. If the value of this
object is absoluteValue, the value of the selected variable is compared
directly with the thresholds at the end of the sampling interval.
If the value of this object is deltaValue, the value of the selected
variable at the last sample is subtracted from the current value,
and the difference is compared with the thresholds. For example, to
set alarmSampleType for alarm #1 to deltaValue, use the following
SNMP Set
request:
snmpset -Os -v2c router community alarmSampleType.1 i deltaValue
alarmValue
The value of the variable during the last sampling period. This
value is compared with the rising and falling thresholds. If the sample
type is deltaValue, this value equals the difference between the samples
at the beginning and end of the period. If the sample type is absoluteValue
, this value equals the sampled value
at the end of the period.
alarmStartupAlarm
An alarm that is sent when this entry is first set to valid.
If the first sample after this entry becomes valid is greater than
or equal to risingThreshold
, and alarmStartupAlarm
is equal to risingAlarm
or risingOrFallingAlarm
, then a single
rising alarm is generated. If the first sample after this entry becomes
valid is less than or equal to fallingThreshold
and alarmStartupAlarm
is equal to fallingAlarm
or risingOrFallingAlarm
, then a single falling alarm is generated. For example, to set alarmStartupAlarm
for alarm #1 to risingOrFallingAlarm
, use the following SNMP Set
request:
snmpset -Os -v2c router community alarmStartupAlarm.1 i risingOrFallingAlarm
alarmRisingThreshold
A threshold for the sampled variable. When the current sampled
value is greater than or equal to this threshold, and the value at
the last sampling interval is less than this threshold, a single event
is generated. A single event is also generated if the first sample
after this entry becomes valid is greater than or equal to this threshold,
and the associated alarmStartupAlarm
is equal to risingAlarm
or risingOrFallingAlarm
. After a rising event is generated,
another rising event cannot be generated until the sampled value falls
below this threshold and reaches alarmFallingThreshold
. For example, to set alarmRisingThreshold
for alarm #1 to 100000
, use the following SNMP Set
request:
snmpset -Os -v2c router community alarmRisingThreshold.1 i 100000
alarmFallingThreshold
A threshold for the sampled variable. When the current sampled
value is less than or equal to this threshold, and the value at the
last sampling interval is greater than this threshold, a single event
is generated. A single event is also generated if the first sample
after this entry becomes valid is less than or equal to this threshold,
and the associated alarmStartupAlarm
is equal to fallingAlarm
or risingOrFallingAlarm
. After a falling event is generated,
another falling event cannot be generated until the sampled value
rises above this threshold and reaches alarmRisingThreshold
. For example, to set alarmFallingThreshold
for alarm #1 to 10000
, use the following
SNMP Set
request:
snmpset -Os -v2c router community alarmFallingThreshold.1 i 10000
alarmOwner
Any text string specified by the creating management application or the command-line interface (CLI). Typically, it is used to identify a network manager (or application) and can be used for fine access control between participating management applications.
alarmRisingEventIndex
The index of the eventEntry object that is used when a rising
threshold is crossed. If there is no corresponding entry in eventTable,
then no association exists. If this value is zero, no associated event
is generated because zero is not a valid event index. For example,
to set alarmRisingEventIndex for alarm #1 to 10
, use the
following SNMP Set
request:
snmpset -Os -v2c router community alarmRisingEventIndex.1 i 10
alarmFallingEventIndex
The index of the eventEntry object that is used when a falling
threshold is crossed. If there is no corresponding entry in eventTable,
then no association exists. If this value is zero, no associated event
is generated because zero is not a valid event index. For example,
to set alarmFallingEventIndex for alarm #1 to 10
, use the following SNMP Set
request:
snmpset -Os -v2c router community alarmFallingEventIndex.1 i 10
Activate a New Row in alarmTable
To activate a new row in alarmTable, set alarmStatus
to valid
using an SNMP Set
request:
snmpset -Os -v2c router community alarmStatus.1 i valid
Modify an Active Row in alarmTable
To modify an active row, first set alarmStatus to underCreation
using an SNMP Set
request:
snmpset -Os -v2c router community alarmStatus.1 i underCreation
Then change the row contents using an SNMP Set
request:
snmpset -Os -v2c router community alarmFallingThreshold.1 i 1000
Finally, activate the row by setting alarmStatus to valid
using an SNMP Set
request:
snmpset -Os -v2c router community alarmStatus.1 i valid
Deactivate a Row in alarmTable
To deactivate a row in alarmTable, set alarmStatus to invalid
using an SNMP Set
request:
snmpset -Os -v2c router community alarmStatus.1 i invalid
Use eventTable to Log Alarms
To use eventTable to log alarms, perform the following tasks:
- Create an Event Entry
- Configure the MIB Objects
- Activate a New Row in eventTable
- Deactivate a Row in eventTable
Create an Event Entry
The RMON eventTable controls the generation of notifications from the router. Notifications can be logs (entries to logTable and syslogs) or SNMP traps. Each event entry can be configured to generate any combination of these notifications (or no notification). When an event specifies that an SNMP trap is to be generated, the trap group that is used when sending the trap is specified by the value of the associated eventCommunity object. Consequently, the community in the trap message will match the value specified by eventCommunity. If nothing is configured for eventCommunity, a trap is sent using each trap group that has the rmon-alarm category configured.
Configure the MIB Objects
Once you have created the new row in eventTable, set the following objects:
The eventType object is required. All other objects are optional.
eventType
The type of notification that the router generates when the event is triggered.
This object can be set to the following values:
log
—Adds the event entry to logTable.log-and-trap
—Sends an SNMP trap and creates a log entry.none
—Sends no notification.snmptrap
—Sends an SNMP trap.
For example, to set eventType
for event #1 to log-and-trap
, use the following SNMP Set
request:
snmpset -Os -v2c router community eventType.1 i log-and-trap
eventCommunity
The trap group that is used when generating a trap (if eventType
is configured to send traps). If that trap group has the rmon-alarm
trap category configured, a trap is sent to all the targets configured
for that trap group. The community string in the trap matches the
name of the trap group (and hence, the value of eventCommunity). If
nothing is configured, traps are sent to each group with the rmon-alarm
category set. For example, to set eventCommunity for event #1 to boy-elroy,
use the following SNMP Set
request:
snmpset -Os -v2c router community eventCommunity.1 s "boy-elroy"
The eventCommunity object is optional. If you do not set this object, then the field is left blank.
eventOwner
Any text string specified by the creating management application or the command-line interface (CLI). Typically, it is used to identify a network manager (or application) and can be used for fine access control between participating management applications.
For example, to set eventOwner for event #1 to george jetson,
use the following SNMP Set
request:
snmpset -Os -v2c router community eventOwner.1 s "george jetson"
The eventOwner object is optional. If you do not set this object, then the field is left blank.
eventDescription
Any text string specified by the creating management application or the command-line interface (CLI). The use of this string is application dependent.
For example, to set eventDescription for event #1 to spacelys
sprockets, use the following SNMP Set
request:
snmpset -Os -v2c router community eventDescription.1 s "spacelys sprockets"
The eventDescription object is optional. If you do not set this object, then the field is left blank.
Activate a New Row in eventTable
To activate the new row in eventTable, set eventStatus to valid
using an SNMP Set
request such as:
snmpset -Os -v2c router community eventStatus.1 i valid
Deactivate a Row in eventTable
To deactivate a row in eventTable, set eventStatus to invalid
using an SNMP Set
request such
as:
snmpset -Os -v2c router community eventStatus.1 i invalid