Spectrum UI displays negative values for Last Change in Interface Configuration Table

Products

• Network Observability

Issue/Introduction

The Spectrum OneClick UI incorrectly displays negative integer values in the Last Change column of the Interface Configuration Table for certain interfaces on Aruba switches. This behavior occurs even when the device returns valid positive TimeTicks via SNMP.​​​​​​​‌​​​​

ERROR MESSAGE: "-[Large Negative Integer]" (e.g., in the Last Change column of the Component Detail > Interface Configuration Table)

SYMPTOMS:

• The Last Change column shows negative values for interfaces with high uptime.

• snmpwalk/snmpget returns a large positive value (e.g., 2541045526).

• The issue is specific to the UI rendering of the ifLastChange attribute (0x100cc).

CONTEXT: This occurs when the raw TimeTick value reaches or exceeds 2,147,483,648 (2^31), causing the high bit to be set.

IMPACT: Users cannot accurately monitor interface state changes in the Spectrum OneClick console.

Environment

 

• OS: Linux RedHat Enterprise Linux 8.9

• UI: DX NetOps Spectrum OneClick

• Device: Aruba Switches

• OID: 1.3.6.1.2.1.2.2.1.9 (ifLastChange)

• DX NetOps Spectrum 24.3.13

 

Cause

The SNMP ifLastChange metric (attribute 0x100cc) is a 32-bit unsigned quantity. The Spectrum UI improperly treats this attribute as a signed integer, causing it to misinterpret the high bit and display large positive values as negative numbers once the value exceeds 2,147,483,648.

RELATED RESOURCES:

• Defect ID: DE184380

• OID: 1.3.6.1.2.1.2.2.1.9 (ifLastChange)

KNOWN LIMITATIONS:

• This is a UI rendering issue only; the underlying data collected from the device is correct.

Resolution

 

• VERIFY RAW DEVICE DATA: Ensure the device is sending correct unsigned integers.

  Command: snmpwalk -Otne -v3 -u [username] -a SHA -A [password] -l authNoPriv [IP-address] 1.3.6.1.2.1.2.2.1.9.1

  EXPECTED: The command returns a large positive integer (e.g., 2541045526).

• IDENTIFY UI RENDERING DEFECT: Confirm that the UI is casting the 32-bit unsigned TimeTicks as signed integers.

  NOTE: When the high bit is set (value > 2^31), a signed interpretation results in a negative display.

• UPGRADE TO RESOLVED VERSION: Engineering has identified the fix (Defect DE184380) which would be part of 25.4.7/8 release( Subject to passing tests)

  ACTION: Apply the upcoming Spectrum release that includes the fix for DE184380.

  EXPECTED: The Last Change column correctly displays 32-bit unsigned integers.