When the link measurement template is assigned to an IP interface, the audit process determines the operational state of the test. The interface delay test transitions to operationally up if the following conditions are met:
The associated measurement template is administratively enabled.
There is an administratively enable test protocol, configured using the ipv4 or ipv6 command.
The system resources are available to start the test.
Further validation determines if there are any underlying conditions that are considered detectable transmission errors, which are listed in Table: Detectable transmission errors .
| Detectable Tx error | Description | Prevents transmission |
|---|---|---|
None |
No detectable errors |
No |
interfaceDown |
The link measurement test is configured on an IP interface with an operationally down state |
Yes |
UnexpectedError |
Router resources not available |
No |
noRoute |
The routing lookup has failed to resolve the destination as reachable from the interface where the test is configured. The packet is transmitted out of the interface resolved by the routing engine. |
No |
sourceIpNotLocal |
The source IP address configured for the test is not local to the system |
No |
invalidDestIp |
The destination IP address is not valid. This may occur because of a configuration error or an attempt to use auto assignment in conditions that are not supported. |
Yes |
invalidInterfaceType |
The link measurement test is configured under an interface that does not support these test types (such as loopback interfaces) |
Yes |
sameSourceIpDestIp |
A configuration error that indicates the source and destination IP addresses are the same |
Yes |
When all audit conditions successfully pass, the delay collection begins. When no thresholds are configured, the test collects delay information as history, but without at least one configured threshold value, reporting updates to the routing engine are disabled. If at least one threshold is configured, the interface enters the first report phase. Because no previous delay value has been reported, the first measurement window with a configured threshold that completes with integrity triggers the delay measurement report. After this benchmark is set, all subsequent thresholds use the delay measurement last reported as the comparison.