SevOne NMS 5.4 Quick Start Guide - SNMP

SNMP Poll Data

Devices for which you enable the SNMP plugin can display metrics for the following common SNMP indicators on the Device Summary.

• CPU Total - Displays the following CPU total data, when available.

  • Name

  • Idle CPU Time

  • Kernel CPU Time

  • Nice CPU Time

  • System CPU Time

  • User CPU Time

  • Waiting CPU Time

• CPU - Displays the following information for each CPU, when available.

  • Name

  • CPU Load

• Memory - Displays the following memory information, when available.

  • Name

  • Description

  • Available Real Memory

  • Available Swap Memory

  • Total Free Memory

  • Total Used Memory

• Disks - Displays the following disk information, when available.

  • Name

  • Description

  • Available Disk Space

  • Used Disk Space

  • Storage Used

  • Used Storage Indicators

  • Hard Drive Storage Used

• Interfaces - Displays the following information for each interface on the device.

  • Interface Name

  • Utilization (In Out)

Manage SNMP Object Types

Perform the following steps to manage SNMP object types.

1. Above the Object Types hierarchy, click Add or click to display the Add/Edit SNMP Object Type pop-up.

2. In the Name field, enter the object type name.

   Each of the following fields has a corresponding check box on the right side to enable you to make changes at this level of the hierarchy and below. The changes you make when you select the right-hand check box override and do not affect the parent object type definition.

3. Click the Indexed By to display the SNMP OID Browser where you select an index OID.

4. Select the Reverse Engineer check box to have instances of this object type be uniquely identified by evaluating the OID of the SNMP object specified in the Indexed By field, as opposed to its value. How the values encoded within the OID are evaluated is based on the configuration of the Index Keys field. You should leave this check box selected for the vast majority of object types.

5. The Index Keys fields enable you to select the index keys to use to determine how to treat the remaining octets after the index. In the Possible Values field, select index keys to assign to the object type (use Ctrl or Shift keys to multi-select) then move the index keys to the Index Keys field. Index keys in the Index Keys field are assigned to the object type and they display in the sequence in which they appear listed. Possible values include the following:

   • Integer - A single number that indicates there is a constant amount of numbers following each OID.

   • String - A string prefixed with the string length. This typically appears with double quotes.

   • String (Implied) - A string with no length information. This must only occur as the last index value.

   • Variable - A variable amount of numbers prefixed with the amount of items. This is typically used for IPv4 versus IPv6 indexes.

   • Variable (Implied) - A Variable amount of numbers, but with no length information. This must occur as the last index value. This can be used to "eat up" the remainder of the index.

6. Click the Name Expression to display the SNMP OID Browser where you select an OID that results in a unique name for all object types on a device.

7. Click the Description Expression to display the SNMP OID Browser where you select an OID to add additional information about the object type.

8. Click the Subtype to display the SNMP OID Browser where you select an OID to define a subtype for the object type (used for thresholds and reports). This can generate the following variables:

   • - [TYPE]: The numerical value of the subtype.

   • - [TYPE]: The name of the subtype.

   • - [TYPE]: The description of the subtype.

9. Click the Assert to display the SNMP OID Browser where you select an OID to use in the assert expression that generates a list of individual object indexes. This is skipped if the object does not pass the assert expression. No variables are generated.

   Example: To match only Ethernet interfaces and ignore everything else, enter the following statement.

   ifType == 6

   This separates memory from disks in the Host Resources MIB; both use hrStorageIndex, but each has a different value for hrStorageType. You should not modify the default Interface definition.

10. Click the Last-change OID to display the SNMP OID Browser where you select an OID for the SNMP plugin to use to determine if a change was made to the object type since it was last polled. If the object type changed, the SNMP plugin invalidates the current data.

11. Click the Admin-status to display the SNMP OID Browser where you select an OID for the SNMP plugin to use to determine the administrative status of the object.

12. Click the Oper-status to display the SNMP OID Browser where you select an OID for the SNMP plugin to use to determine the operational status of the object.

13. In the Variable field, enter the variables, expressions, and operators to you want the SNMP plugin to evaluate first for use with the other fields.

14. Click Edit Subtypes to display the Object Subtype Manager where you manage the object subtypes.

15. Click Save.

16. In the Object Types hierarchy, click to select the object type to which to associate device types.

17. In the Device Type section on the right, click Associate to display a pop-up that enables you to associate the SNMP object type with device types on which you want to poll data.

    1. Select the check box for each device type to which to associate the object type.

    2. Click Associate to create the association and to close the pop-up.

Manage SNMP Indicator Types

Indicator types determine what indicators are polled for an object type. The indicator types list displays the indicator types for the object type you select in the Object Types hierarchy. There are two types of indicator types.

• Atomic indicator types are measured directly by the plugin.

• Synthetic indicator types are indicators whose value is dependent upon other indicators; atomic and/or synthetic. Synthetic indicators enable you to combine the data from several indicators into one synthetic indicator so that SevOne NMS can properly evaluate indicators such as Percentage Loss, Percent Error, Percent Idle, and other high precision metrics.

Manage SNMP Object Subtypes

The Object Subtype Manager enables you to manage the object subtypes that group the objects you want the SNMP plugin to poll.

Perform the following steps to manage SNMP object subtypes.

1. From the navigation bar, click the Administration menu, select Monitoring Configuration, and then select Object Subtype Manager. You can also access the Object Subtype Manager from the Object Types page.

2. Click the Plugin drop-down and select SNMP Poller.

3. Click the Object Type drop-down and select an object type to display its object subtypes in the list.

4. Click Add Subtype or click to display the Object Subtype Editor pop-up.

5. In the Name field, enter the name of the object subtype.

6. In the Description field, enter the object subtype description.

7. Select the Is Common check box to enable the objects associates with the subtype to appear in lists of common objects.

8. Click Add to add a new line to the Rules list.

9. In the Identifier field, enter the string to match in order to apply the rule.

10. Click Update to save the rule.

11. Repeat the Add steps to define additional rules. Each rule is evaluated and appropriate rules are applied.

12. Click Save.

MIB Manager

The MIB Manager enables you to view MIB details and to add MIBs. MIBs are the files that enable the raw machine generated OIDs to display in a way that is more understandable to users. For a list of MIBs and MIB definitions, visit www.mibsearch.com. SevOne NMS provides a list of standard MIBs.

To access the MIB Manager from the navigation bar, click the Administration menu, select Monitoring Configuration, and then select MIB Manager.

The list displays the following MIB information.

• Name - Displays the MIB name.

• Size - Displays the size of the MIB file.

• Revision - Displays the number of times you upload the MIB to SevOne NMS.

• Date Added - Displays the date the MIB was added.

• Date Updated - Displays the date the MIB was most recently edited.

The following controls enable you to manage MIBs.

• Select the check boxes for the MIBs to manage and click .

  • Select Add MIBs to open the MIB Uploader.

  • Select Delete Selected MIBs to remove the MIBs

  • Select Download All MIBs to create a .zip file of all MIBs that you can download for email, backup, etc.

  • Select Download Selected MIBs to open and view the MIB files or to save the MIBs to your computer.

  • Select Delete Selected MIBs to remove the MIBs.

• Click Add MIBs to display the MIB Uploader pop-up.

  1. Click Select MIB(s) to display the File Uploader pop-up.

  2. Navigate to the MIB file to upload and select it. To add multiple MIBs, zip the MIB files into a .zip format file and select the .zip file.

  3. Click Open on the File Uploader pop-up.

  4. Click Upload on the MIB Uploader pop-up.

• Click Download All MIBs to create a .zip file of all MIBs that you can download for email, backup, etc.

SNMP OID Browser

The SNMP OID Browser enables you to select the OID you use to create SNMP object types and SNMP traps.

You can access the SNMP OID Browser from the navigation bar, click the Administration menu, select Monitoring Configuration, and then select SNMP OID Browser. Typically you access the SNMP OID Browser from an SNMP object type definition workflow or from a trap event configuration workflow. When an applicable OID appears on the right, click Select OID to return to the Object Types page.

The OID Tree section displays the OID hierarchical structure. The Search field enables you to filter the list of OIDs by name or by number. Navigate the OID tree hierarchy and select an OID to display more information on the right. The OID Information section displays the following information.

• Name - Displays the OID name.

• OID - Displays the OID number.

• Access - Displays the type of access available for the OID such as Read, Read/Write, etc.

• Type - Displays how the OID appears such as String, Integer, etc.

• Status - Displays the OID status such as Current, Deprecated, or 0 (no status).

• Description - Displays the OID description.

SNMP Walks

The textual name of an OID is only unique in the MIB to which it belongs so OIDs are accurately written as follows: <MIB Name>::<OID name>

• snmpget - When a device is queried for an OID.

• snmpwalk - When a device is queried for an OID and all of its conceptual children.

• snmpset - When the value for an OID is set on a device.

In the case of interfaces (and most SNMP objects), an OID is dedicated to providing the index number.

The value of each OID is also the index, which simplifies how to obtain the proper indexes.

The SNMP Walk page enables you to walk MIBs. The MIB does not need to be in SevOne NMS to perform a walk which is useful when you want to certify a MIB.

To access the SNMP Walk page from the navigation bar, click the Devices menu and select SNMP Walk. You can also access the SNMP Walk page from the Device Manager.

When you access the SNMP Walk page from the Device Manager, some of the following fields are pre-populated.

1. In the IP Address/Hostname field, enter the IP address or Hostname of the device.

2. In the SNMP Port field, enter the port on which the device is listening for SNMP traffic.

3. Click the SNMP Version drop-down and select the SNMP version of the device.

4. In the Read Community String field, enter the read community string of the device.

5. Click the SNMP Command drop-down.

   • Select snmpwalk to query a device for an OID and all of its conceptual children.

   • Select snmpget to query the device for an OID.

6. In the OID field, enter the OID to walk. If you leave this to the default OID, the walk may take a while. Be specific with your search. You should use ".1.3" or ".1.3.6" to avoid partial or broken walks.

7. Click the Output Format drop-down.

   • Select Default to display OIDs in text format (e.g. IF-MIB::ifInErrors.1).

   • Select Default With Numeric Indexes to translate strings to ASCII numeric values.

   • Select Numeric OIDs to translate OIDs into numeric format (e.g. .1.3.6.1.2.1.2.2.1.14.2).

   • Select Certification Walk to translate OIDs into a form that SevOne Support Engineers can use to perform device certifications.

8. Click the Source Peer drop-down and select the peer to perform the walk.

9. Click Walk to perform the SNMP walk.

10. After the walk performs, click Select Result Text to copy the results to your computer clipboard so you can paste the results into an email or document etc.

Conceptualize Objects, SNMP Walks

The following is a sample SNMP walk of the RFC1213 MIB for a particular device to illustrate what a sample SNMP walk may look like.
RFC1213-MIB::ifIndex.1 = INTEGER: 1
RFC1213-MIB::ifIndex.2 = INTEGER: 2
RFC1213-MIB::ifIndex.8 = INTEGER: 8
RFC1213-MIB::ifDescr.1 = STRING: "Ethernet3/0"
RFC1213-MIB::ifDescr.2 = STRING: "Serial3/0"
RFC1213-MIB::ifDescr.8 = STRING: "Loopback0"
RFC1213-MIB::ifType.1 = INTEGER: ethernet-csmacd(6)
RFC1213-MIB::ifType.2 = INTEGER: frame-relay(32)
RFC1213-MIB::ifType.8 = INTEGER: softwareLoopback(24)
RFC1213-MIB::ifSpeed.1 = Gauge32: 10000000
RFC1213-MIB::ifSpeed.2 = Gauge32: 1544000
RFC1213-MIB::ifSpeed.8 = Gauge32: 4294967295
RFC1213-MIB::ifPhysAddress.1 = Hex-STRING: 00 30 80 F3 1F F1
RFC1213-MIB::ifPhysAddress.2 = ""
RFC1213-MIB::ifPhysAddress.8 = ""
RFC1213-MIB::ifAdminStatus.1 = INTEGER: up(1)
RFC1213-MIB::ifAdminStatus.2 = INTEGER: up(1)
RFC1213-MIB::ifAdminStatus.8 = INTEGER: up(1)
RFC1213-MIB::ifOperStatus.1 = INTEGER: up(1)
RFC1213-MIB::ifOperStatus.2 = INTEGER: down(2)
RFC1213-MIB::ifOperStatus.8 = INTEGER: up(1)
RFC1213-MIB::ifInOctets.1 = Counter32: 1890978658
RFC1213-MIB::ifInOctets.2 = Counter32: 0
RFC1213-MIB::ifInOctets.8 = Counter32: 0
RFC1213-MIB::ifInDiscards.1 = Counter32: 85
RFC1213-MIB::ifInDiscards.2 = Counter32: 0
RFC1213-MIB::ifInDiscards.8 = Counter32: 0
RFC1213-MIB::ifOutOctets.1 = Counter32: 2071381140
RFC1213-MIB::ifOutOctets.2 = Counter32: 0
RFC1213-MIB::ifOutOctets.8 = Counter32: 2819292
RFC1213-MIB::ifOutDiscards.1 = Counter32: 0
RFC1213-MIB::ifOutDiscards.2 = Counter32: 0
RFC1213-MIB::ifOutDiscards.8 = Counter32: 0

All of these OIDs refer to three interfaces, identified by the final number of each OID; in this case 1 (for Ethernet3/0), 2 (for Serial3/0), and 8 (for Loopback0). The information about each particular interface is interleaved with that of the others.
Perform the following steps to find out whether Ethernet3/0 is up or down.

1. Search every ifDescr entry until you fine the one whose value matches Ethernet3/0.

2. Remember the index (the last number) for it.

3. Check the value for ifOperStatus using that index.

Manage Device Type Hierarchy

The device type hierarchy appears on the left. There are two first level device types; SevOne Device Types and Custom Device Types. SevOne Device Types provide common, logical, poll focused, collections of devices that are used in starter set reports, policies, etc. You cannot edit or delete the SevOne Device Types. Custom Device Types provide the ability to monitor more diverse devices and cutting edge technologies. Check boxes enable you to simultaneously manage the metadata values, drag and drop, and delete multiple device types.

1. Select the custom device type under which to add a new device type.

2. Click Add Device Types to display a pop-up.

   1. In the Device Type Name field, enter the device type name.

   2. Click Save on the pop-up.

3. - Click to edit the values for the metadata attributes you want to associate with the device types. See the Manage Metadata Values section below.

4. - Click to edit a device type name.

5. Drag and drop device types to different places in the custom device type hierarchy.

6. - Click to delete the device group. When you delete a device group that has associated policies, a message appears to inform you that associated policies will be deleted.

   1. On the message, click View Policies to display the Policy Association pop-up that lists the policies associated to the device group.

   2. Select the policies to move and click Reassign Selected or click Reassign All to display a pop-up that enables you to select the device group to which to move the policies.

   3. On the pop-up, click the drop-down and select the device group to which to move the policies and click OK.

   4. Click Done to move the policies.

Device Type Membership Rules

Click on a device type in the hierarchy to display the device type membership rules in the upper section on the right. Membership rules enable you to automatically add devices to the device type when the SNMP plugin discovers devices that contain objects that meet the rule criteria.

1. Click Add Rule or click to display the Add/Edit Device Type Membership Rule pop-up. Each rule requires only one field. If you populate several fields per rule, the criteria you enter in that rule are cumulative.

   Example: Enter Remote in the Name field and enter ^192\.168 in the Management IP Address field in the same rule criteria row. The device must have both Remote in the name AND an IP address that starts with 192.168 to be added to the device type.

   • Device Name - Enter the name of the devices to add to the device type (wild cards are implied).

   • Device Description - Enter the description of the devices to add to the device type.

   • Management IPAddress - Enter the IP address of the devices to add to the device type (^192\.168 adds all devices whose IP address starts with 192.168).

   • sysDescr - Enter the text you get when you SNMP walk the sysDescr OID.

   • sysContact – Enter the text you get when you SNMP walk the sysContact OID.

   • sysLocation - Enter the text you get when you SNMP walk the sysLocation OID.

   • sysName – Enter the text you get when you walk the sysName OID.

   • sysObjectID - Enter the text you get when you SNMP walk the sysObjectID OID.

   • Walkable OID – Enter the number of the OID to walk.

2. Click Save to save the rule criteria.

Repeat these steps to add additional rules to use the OR Boolean.

Object Types

The Object Types tab in the lower right section contains two groups of object types Inherited and Local. The Object Types tab displays the following information.

• Object Type - Displays the name of the object type.

• Plugin - Displays the name of the plugin that polls the object type.

• Defined In - Displays Local for object types that are defined at this level in the Device Type hierarchy or displays a link that navigates you to the level in the Device Types hierarchy from where the object type inherits its definition.

The Object Types tab enables you to associate the SNMP object types you want the SNMP Plugin to attempt to poll on the devices that are members of the device type.

1. On the Object Types tab, click Associate to display the Associate pop-up.

2. Select the check box for each object type to poll on the devices that are members of the device type.

3. Click Associate on the pop-up to associate the object types to the device type.

Device Type Membership

The Device Type Membership tab displays the devices that are members of the device type. When you pin a device to a device type, rules do not affect the device's membership and you must manually unpin the device to remove its membership. When a rule adds a device to a device type, if you change the rule, the devices that were added by the rule can automatically be removed from the device type.

• - Indicates the device is a member that was pinned to the device type at this level.

• - Indicates the device is a member that was pinned to a lower level device type.

• – Indicates the device is a member that was added by a device type membership rule at this level.

• - Indicates the device is a member that was added by a device type membership rule at a lower level.

Logged Traps

The Logged Traps page displays the SNMP traps SevOne NMS receives for which you define a trap event. Logged traps have a trap event. The Cluster Manager enables you to define how long to save logged traps.

To access the Logged Traps page from the navigation bar, click the Events menu, select Archives, and then select Logged Traps.

The logged traps list displays logged traps from most recent to oldest. Filters enable you to limit the traps that appear in the list. All filters are optional and cumulative.

• IP Address - Displays the IP address from where the trap was sent.

• Time - Displays the time SevOne NMS received the trap.

• OID - Displays the trap's object identifier (OID) that met the conditions for the trap event.

• Variable Number - Displays the number of variable conditions associated with the trap.

Click on a trap to display the following information in the Variable Conditions section.

• Variable - Displays the name of the variable.

• Type - Displays the variable type.

• Value - Displays the value that triggers the trap.

Unknown Traps

The Unknown Traps page displays the SNMP traps for which no trap events apply. The traps that appear on the Unknown Traps screen are less meaningful than traps for which you define a trap event. Trap events enable you to assign real meaning to SNMP traps. The goal is to enable you to define trap events (either ignore, log, or alert) for the traps that are specific to your environment. The Cluster Manager enables you to define how long to save unknown traps.

To access the Unknown Traps page from the navigation bar, click the Events menu, select Archives, and then select Unknown Traps.

The unknown traps list displays traps from most recent to oldest. Filters enable you to limit the traps that appear in the list. All filters are optional and cumulative.

• IP Address - Displays the IP address from where the trap came.

• Time - Displays the time SevOne NMS received the trap.

• OID - Displays the trap's object identifier (OID) that could be used to define a trap event.

• Variable Number - Displays the number of variable conditions associated with the traps.

Click on a trap to display the following in the Variable Conditions section.

• Variable - Displays the name of the variable with a check box. Select the check box to include the variable in the trap event definition.

• Type - Displays the variable type.

• Value - Displays the value that triggers the trap.

The Configure Trap Event button enables you to define a trap event for the unknown trap. After you define the trap event, the trap is handled in the way you specify and future trap occurrences appear on the Logged Traps page, when applicable.

1. Select a trap in the list.

2. Select the check boxes for the variables to include in the trap event definition.

3. Click Configure Trap Event to display the Trap Event Editor with applicable fields pre-populated.

Trap Event Editor

The Trap Event Editor enables you to configure how to handle traps. Traps that you associate to a trap event can appear on the Logged Traps page and traps without a trap event appear on the Unknown Traps page. SevOne NMS provides a collection of common, default trap events.

To access the Trap Event Editor from the navigation bar, click the Events menu, select Configuration, and then select Trap Event Editor. Typical access to the Trap Event Editor is from the Unknown Traps page that provides a Configure Trap Event button.

Each trap has a primary OID that designates the trap type. Each trap event has a target OID. When the trap primary OID matches the trap event target OID and any trap event variable conditions you define, the trap triggers the trap event.
Filters enable you to limit the trap events that appear in the list. All filters are optional and cumulative.

There are several paths to access the Event Editor pop-up dialog that enables you to create and edit trap events.

1. Click Add Trap Event, click to edit a trap event or from the Unknown Traps page, select an unknown trap and click Configure Trap Event.

2. Select the Enabled check box to enable the trap event. Leave clear to not apply the trap event and to display applicable traps on the Unknown Traps page.

3. The Match options enable you to apply the trap event to a specific OID, device groups, devices, or operating systems. Matching is a logical OR option, meaning that the trap primary OID must come from the specified device group, device, or operating system to trigger the trap event. To make the trap event applicable for all device groups, devices, and operating systems, do not define any Match options.

   • The Target OID field provides an to access the SNMP OID Browser where you select the target OID for the trap event. When you edit a trap event or you access the Trap Event Editor from the Unknown Traps page, this field displays the name of the OID you select. You can enter the OID name in this field if you know the OID name.

   • Click the Device Groups drop-down and select the check boxes for the device groups to associate with the trap event.

   • Click the Devices drop-down and select the devices to associate with the trap event.

   • Click the Operating System drop-down and select the operating systems to associate with the trap event.

4. The Variable Conditions field enables you to define the conditions for which the trap event is applicable.

   1. Click Add to add a row to the table and to define a new variable condition.

   2. Click in the OID field to display the SNMP OID Browser where you select the trap target OID.

   3. Click the Op drop-down and select a comparison operator.

   4. In the Value field, enter the value that must be met to associate the trap to the trap event.

   5. Click Update to save the OID with the trap event.

5. The Unique OIDs field enables you to designate unique OIDs to associate to the trap event.

   1. Click Add to add a row to the table and to add an OID.

   2. Click in the OID field to display the SNMP OID Browser where you select the OID.

   3. Click Update to save the OID with the trap event.

6. Select the Log check box to display the trap on the Logged Traps page. All traps received appear on either the Unknown Traps page or the Logged Traps page. To have a trap not appear on either of these pages, define an enabled trap event and leave this check box clear.

   Example: For devices that send traps when traffic is denied through a firewall rule, a logged trap enables you to trace the events to a firewall to determine the cause of missed traffic. Frequent but irrelevant traps such as when devices send traps each time a new IP address is leased via DHCP may not be useful.

7. Select the Alert check box to have the trap trigger an alert.

   1. Click the drop-down and select the alert severity to display for the alert.

   2. In the text field, enter the message to appear for the trap when the trap event triggers. You can use the following variables in the message.

      • $dev - To display the name of the device from which the trap came.

      • $oid - To display the trap OID in name format.

      • $oidnum - To display the trap OID in number format.

      • $var - To display the variable condition for the trap in name format.

      • $varnum - To display the variable condition for the trap in number format.

8. Select the Email check box to enable the following fields.

   • Select the Mail Once check box to send one email when a trap triggers the first occurrence of the trap event. All subsequent occurrences are not emailed.

   • Click the Users drop-down and select the users to receive an email when the trap event triggers.

   • Click the Roles drop-down and select the user roles to receive an email when the trap event triggers.

   • In the Email Addresses field, click Add to enter the email addresses where an email is to be sent when the trap event triggers.

9. Click Save.

Trap Destinations

The Trap Destination page enables you to define the destinations where you want SevOne NMS to send traps. Trap destinations can be third party applications such as your company's event console or fault management system. Each trap can be sent to multiple destinations.

To access the Trap Destination page from the navigation bar, click the Events menu, select Configuration, and then select Trap Destinations.

1. - Click the Action icon and select Add New Destination or select the check box for a destination to edit then click Edit Selected to display the Trap Destination Settings pop-up.

2. In the Name field, enter the trap destination name.

3. In the IP Address field, enter the IP address of the trap destination device.

4. In the Port Number field, enter the port number to which to send the trap.

5. In the SNMP Read Only Community String field, enter the read only community string SevOne NMS needs to authenticate onto the device.

6. Click the SNMP Version drop-down and select an SNMP version.

7. Select the Default check box to send traps to the destination by default. You can designate multiple default trap destinations and you can define individual thresholds and policies to not use a default destination for specific traps when you define thresholds and policies.

8. Select the Enable check box to enable the trap destination.

9. Click Save.

Trap Destination Associations

The Trap Destination Associations page enables you to associate devices or device groups with the trap destinations you define on the Trap Destinations page. SevOne NMS sends traps from devices or device groups to their associated trap destinations. Trap destinations can be applications such as your company's third party event console or fault management system.

To access the Trap Destination Associations page from the navigation bar, click the Events menu, select Configuration, and then select Trap Destination Associations.

1. Click the Grouping drop-down.

   • Select Device Group to associate all the devices in a device group to trap destinations.

   • Select Device to associate an individual device to trap destinations.

2. Click the Device Group/Device drop-down and select the device group or the device to which to associate trap destinations.

3. In the Unassigned Trap Destinations field, select the trap destinations (use the Ctrl or Shift keys to multi-select) to associate to the device group or device.

4. - Click to move the trap destinations you select to the Assigned Trap Destinations field. Traps are sent from the device group or device to the trap destinations in the Assigned Trap Destinations field.

5. Select a trap destination in the Assigned Trap Destinations field and click Disable to save the trap association but suspend sending traps to the destination. Disabled trap destinations appear in light text.

6. Select a disabled trap destination in the Assigned Trap Destinations field and click Enable to enable the association.

How OIDs Are Indexed

Device manufacturers name SNMP OIDs by a series of numbers, (e.g., The OID sysDescr is .1.3.6.1.2.1.1.1). Everything that comes after a named OID is the OID index. System wide information is usually denoted as .0 information. The .0 generally means there is only one instance of the OID, (e.g., The sysDescr index is always .0). The OID ifDescr is indexed by a single number that is not 0, (e.g., The description of an Ethernet card in a server might be ifDescr.3). There is no limit to the count of numbers that follow an OID. Some manufacturers use integer indexes that have a constant amount of numbers that follow each OID and some manufacturers use string indexes for readability. A string index represents a piece of text (the string) as a series of characters where each character is represented as its ASCII value. String indexes are sometimes prefixed with the length of the string.

Scripts

An S3 script is a sequential evaluation of one or many statements. Each statement is executed in sequence. The only logic provided by S3 comes from flavors of the ternary operator which acts like an IF statement. The final result of the script is the result of the final statement in the script.

Example 1:

Statement 1

Example 2:

1. Statement 1

2. Statement 2

3. Statement 3

S3 OID Handling

OIDs are evaluated. Anything that is not text, a variable, an operator, a normal number, or otherwise special symbol is considered an OID. When an OID is evaluated, it evaluates to the value of the OID on the current device. If the OID is not present on the device, the OID, followed by the default SNMP index, is used instead. If the OID cannot be evaluated, it evaluates to the empty string.

It is critical to note here that a variable without back ticks around it is treated exactly as it would if the value of the variable were to be placed in its stead. This means that a variable that contains a string representation of an OID is evaluated as that OID when it is encountered.

The following example might not work as expected:

1 [test] = 'test';
2 [test1] = [test] 1;

One might expect the value of "[test1]" to be "test1"; however, since "[test]" is not back ticked, it is treated as if the text "test" were present. As such, S3 tries to get the value of the OID whose name is "test" naturally, there is not one, and it returns the empty string. Thus, the final value is actually "1".

The proper way to do this is:

1 [test] = 'test';
2 [test1] = `[test]` 1;

This example back ticks the variable to prevent it from being evaluated as an OID.

Symbols

Symbols are special tokens (characters, or collections of characters) that have a special function in S3.

Precedence

The precedence of operators and symbols is as follows. When given the choice (in other words, when parentheses are not used), S3 evaluates operations in the following sequence.
The normal mathematical operator precedence (* / + -) is preserved in this list.

1. 'text' `text`

2. ()

3. #s #S #v #V $s $S $v $V

4. * /

5. + -

6. == != > >= < <=

7. &&

8. ||

9. |||

10. :

11. ? ??

12. =

Variable Assignment Example

The following examples assign the proper values to variables whose name should match their value.

1. [one] = 1;

2. [two] = 1 + 1;

3. [two] = `[one]` + `[one]` - 1 + 1;

4. [ten] = ( 2 + 1 ) * 3 + 1;

The following example sets all three variables equal to 12.

1 [x] = [y] = [z] = 12;

Full Examples

Object context

The main purpose of S3 is to define ways to describe specific objects from a generic set of rules. As the SNMP discover script goes through the possible object types, for each one, it generates a list of individual object indexes for that object type. The rules for that object type are applied to each index that it encounters, generating a unique object per index.

The following SNMP Object Editor fields are evaluated, in order, for each object:

1. Variables

   • A mini S3 script generates variables for later use.

   • Variables generated:

     • (Any present)

2. Subtype expression

   • Determines the subtype of the object.

   • Variables generated:

     • [TYPE]: The numerical value of the subtype (if any).

     • [TYPE NAME]: The name of the subtype (if any).

     • [TYPE DESCRIPTION]: The description of the subtype (if any).

3. Assert expression

   • Skipped if an object does not pass the assert expression.

   • Should not define any variables.

4. Name expression

   • Uniquely identifies an object across the SNMP plugin for the device in question.

   • Should not define any variables.

5. Description expression

   • Should provide an informative description of the object. If not set then use the object type.

   • Should not define any variables.

Before any evaluation happens, the "[INDEX]" variable is set to the SNMP index of the current object. This is a vector variable; each index in the vector corresponds with each specific index key defined for this object type. Each of those could also be a vector. Because of the sequence in which the system variables are generated; S3 generates an error if a variable is used before it is generated.

Indicator context

The Expression field in the SNMP Indicator Editor for a particular indicator is also an S3 expression. Indicators should not set variables. The Maximum Value Expression field is also an S3 expression.

An indicator expression and maximum value expression can use any of the variables defined above for the object, including any user-defined variables in the Variables field.

This enables an indicator definition to get around any strange indexing (including out-of-order indexing) by using S3 to assemble the OID to poll as necessary.

Cannot See Interfaces

You may not see an interface because SevOne NMS cannot SNMP walk the device due to an incorrect community string. Perform the following steps to verify the SNMP community strings for the device are correct.

1. Go to the Device Manager.

2. - Click next to the device to edit to display the Edit Device page for the device in question.

3. On the SNMP plugin, verify the community string and SNMP version are correct.

4. If they are correct, log on to the device and enter the following command to walk the device: snmpwalk -v<version> -c<community string> <ip address> (If the SNMP version is 2c, use 2 for the version.)

5. If the command fails, then SevOne NMS cannot SNMP walk the device. Try to walk the device from another location to ensure that the device is properly configured.

Common reasons for not being able to SNMP walk a device include:

• Routing - There is no route from SevOne NMS to the device.

• Firewall - A router between SevOne NMS and the device blocks SNMP traffic.