user manual

4-5
Cisco Active Network Abstraction Fault Management User Guide, Version 3.6 Service Pack 1
OL-14284-01
Chapter 4 Advanced Correlation Scenarios
IP Interface Failure Scenarios
Where there is a multipoint setup and only some circuits under an IP interface go down, and this does
not cause the state of the IP interface to change to down, then no “ip interface status down” alarm is
created. All the circuit down syslogs correlate by flow to the possible root cause, for example, Device
unreachable on a customer edge (CE) device.
All IP Interfaces Down Alarm
• When all the IP interfaces configured above a physical interface change their state to down, the All
ip interfaces down alarm is sent.
• When at least one of the IP interfaces changes its state to up, a clearing (active ip interfaces found)
alarm is sent.
• The ip interface status down alarm for each of the failed IP interfaces is correlated to the All ip
interfaces down alarm.
Note When an All ip interfaces down alarm is cleared by the active ip interfaces down alarm but there are still
correlated ip interface status down alarms for some IP interfaces, the severity of the parent ticket is the
highest severity among all the correlated alarms. For example, if there is an uncleared interface status
down alarm, the severity of the ticket remains major, despite the fact that the Active ip interfaces found
alarm has a cleared severity.
The All ip interfaces down alarm is sourced to the Layer1 component. All alarms from “the other side”,
for example, device unreachable correlate to the All ip interfaces down alarm.
IP Interface Failure Examples
Note In all the examples that follow it is assumed that the problems that result in the unmanaged cloud, or the
problems that occurred on the other side of the cloud (for example, an unreachable CE device from a
provider edge (PE) device) cause the relevant IP interfaces’ state to change to down. This in turn causes
the ip interface status down alarm to be sent.
If this is not the case, as in some Ethernet networks, and there is no change to the state of the IP interface,
all the events on the subinterfaces that are capable of correlation flow will try to correlate to other
possible root causes, including “cloud problem”.
Table 4-2 All IP Interfaces Down
Name Description Ticketable Correlation allowed Correlated to Severity
All ip interfaces
down/Active ip
interfaces found
Sent when all the IP interfaces
configured above a physical port
change their oper status to down
Yes Yes Link
Down/Configuration
Change
Major