A tunnel link goes down however, Spectrum doesn't generate alarm on this link, even though ifAdminStatus is "up" and ifOperStatus is "down". When checking the attributes, ok_to_poll is set to yes, GeneratePortStatusAlarm to yes, and PollPortStatus to yes.
Instead of generating an alarm, the link status changes to suppressed. Why?
Spectrum 10.x
This is due to the combination attributes (described below) being set on the interface model.
In Spectrum, in the Information tab for of an interface model, there is a subview labeled "Alarm Configuration". In this "Alarm Configuration" subview are the following two entries:
Generate Alarm on Port - Default value is Yes
Generate Alarm on Device - Default value is No
The Generate Alarm on Port is associated with the GeneratePortStatusAlarms Attribute ID: 0x12a54 which indicates whether a port status alarm is generated on this port or not, specifically the Critical BAD LINK DETECTED alarm. When Generate Alarm on Port is set to Yes and at least one of the following is enabled, a BAD LINK DETECTED alarm will be asserted on the interface model by Spectrum:
PollPostStatus
Live Links (Pipes)
Link Down Trap
Port Fault Correlation
When Generate Alarm on Port is set to No, a BAD LINK DETECTED alarm will not be asserted on the interface model by Spectrum even if at least one of the above is enabled.
The Generate Alarm on Device is associated with the AssertLinkDownAlarm Attribute ID: 0x12957 which determines whether Spectrum generates a Minor (yellow) alarm on the device model when a link-down trap is received for this port. This is different from the Critical BAD LINK DETECTED alarm that can be generated on the interface model when a link down trap is received.
Check over these settings to ensure they're set correctly for your purpose.
Another Knowledge Base (KB) article describes these attributes:
https://ca-broadcom.wolkenservicedesk.com/external/article?articleId=39093