Interface CurrentUtilization is not populated

Products

VMware Smart Assurance VMware Telco Cloud Service Assurance

Issue/Introduction

Different reasons Interface's current utilization is not populated

Environment

Smarts - 10.x

TCSA - 2.x

Resolution

The most common reason for the current utilization value not being populated is that the performance instrumentation is not created for an interface.

To check if performance instrumentation is created for an interface, use the following dmctl command:

dmctl -s <IPDomain> get Interface::<InstanceName>::InstrumentedBy |grep Performance

Smarts IP Manager will not create performance instrumentation for interfaces under the following circumstances:

Octet counters are missing

ifInOctets, IfOutOctets counters must be populated along with the IfSpeed counter:

- ifOutOctets = .1.3.6.1.2.1.2.2.1.16. <InterfaceIndex>
- ifInOctets = .1.3.6.1.2.1.2.2.1.10. <InterfaceIndex>
- IfSpeed = .1.3.6.1.2.1.2.2.1.5. <InterfaceIndex>

High speed interfaces, such as gigabit interfaces use 64 bit octet counters. All 64 bit octet counters can be found with OIDs that start with the sequence 1.3.6.1.2.1.31 (IF-MIB):

- ifHCOutOctets = 1.3.6.1.2.1.31.1.1.1.10.<InterfaceIndex>
- ifHCInOctets = 1.3.6.1.2.1.31.1.1.1.6. <InterfaceIndex>
- ifHighSpeed OID = 1.3.6.1.2.1.31.1.1.1.15. <InterfaceIndex>

If these OIDs are missing or do not have a value, then we cannot poll for the counter values and the performance instrumentation will not be created. IfSpeed value must be greater than 0.

Please see chart below for information on when the instrumentation will be created for regular MIB2 counters and high speed counters.

Basically, the chart shows that if the interface speed, as reported by the IfSpeed and ifHighSpeed OIDs, is less than 20Mbps, MIB2 counters are used only(ifInOctets, IfOutOctets). If the interface speed is between 20Mbps and 650Mbps, both MIB2 and ifMIB(ifHCInOctets, ifHCOutOctets) counters are used. If the interface speed is greater that 650Mbps, only ifMIB counters are used.

Speed	`0`	`X < 20 Mbps`	`20 Mbps < X < 650 Mbps`	`X > 650 Mbps`
`High Speed`	`0`	`X < 20 Mbps`	`20 Mbps < X < 650 Mbps`	`X > 650 Mbps`
`Does Not Exist`	`N.I.`	`MIB2`	`N.I.`	`N.I.`
`Y = 0`	`N.I.`	`MIB2`	`N.I.`	`N.I`
`Y < 20 Mbps`	`N.I.`	`MIB2`	`N.I.`	`N.I.`
`20 Mbs < Y < 650 Mbps`	`N.I.`	`N.I.`	`MIB2 and ifMIB`	`N.I.`
`Y > 650 Mbps`	`ifMIB`	`ifMIB`	`ifMIB`	`ifMIB`

* X: ifSpeed, Y: IfHighSpeed
* N.I. --- No Instrumentation.
*
* The above matrix is implemented when HCOctets are present. When they
* are not present, only MIB2 instrumentation remains as from previous
* matrix and rest all becomes N.I.
*/

Workaround for missing If-MIB (high speed) counters:
The setting: FallbackInterfaceMonitoringToMIB2 is configured in the tpmgr-param.conf file, located at:
```
<IP>/smarts/local/conf/discovery/
```
By default this setting is FALSE. This setting is available as a workaround for missing If-MIB counters when interfaces have MaxSpeed greater than 20Mbps.
> If this value is set to TRUE the IP Manager is forced to use 32-bit counters to monitor greater-than-20-Mbps interfaces when 64-bit counters are not available in the devices MIB.
> If this value is set to FALSE the IP Manager resorts to its default behavior: Do not monitor greater-than-20-Mbps interfaces when 64-bit counters are not available in the MIB.

Polling and Thresholds configured incorrectly
To check this, open the Domain Manager Administration Console, attach to the IP domain and click on the Polling and Thresholds button. Check the following:
Interface group needs to have the Performance setting:
Click Threshold tab and drill into the Interface Group. Drill into the group that this interface is a member of (if unsure, check the members list to ensure that this interface is present). Once the correct group is found, drill into Settings and ensure that the Interface/Port Performance setting is added to the group.
UtilizationThreshold for this interface must be less than 100%:

Drill into Settings and the Interface/Port Performance setting. The UtilizationThreshold value is at the bottom of the window.
Interface Duplex Mode must be specified
Duplex mode must be available for the current utilization calculation. Please see page 78 of the IP reference guide for information on how duplex mode is generated if it is unavailable from device MIBs.
VLAN Interfaces.
By design we do not create Performance Instrumentation for VLAN Interfaces. The way we identify whether a particular Interface is a VLAN Interface or not is by the Interface Description. So if the Interface Desciption has the Keyword VLAN, then we do not create Performance Instrumentation for those Interfaces.
Sub-Interfaces
Current Utilization is not calculated for sub-interfaces by default. It is disabled. This can be enabled in the Polling and Thresholds section of the Domain Manager Administration Console:
- Open the Domain Manager Administration Console via Windows or via the Web-Console.
- From the tool bar, click on configure and select Polling and Thresholds.
- Select the Thresholds Tab in the bottom left corner. Underneath the domain tree, click the plus sign for Interface Groups.
- Select an Interface and click on the plus sign.
- Click the plus sign to the left of Settings.
- Select Ethernet Interface/Port Performance.
- Scroll to the top of AnalysisModeofSubInterfacePerformance.
- Click on the drop down menu and select enable.
- Reconfigure the AMPM domain for the settings to take effect.