Starting with IRP 3.8 IRP adds excessive loss circuit issues detection features.
Circuit issues detection feature is available for transit providers only.When this feature is enabled for a provider IRP uses past probing data to detect when it suffers from excessive levels of packet loss. To determine excessive loss IRP compares a provider’s average loss over an immediate past time horizon, number of probes and average loss difference from other providers. Depending on packet loss thresholds IRP can attempt different actions on the network.
Every time a circuit issue is detected IRP will raise corresponding alerts that can be subscribed to. Network engineers or external network management systems can act on them.
Additionally IRP even though it is constrained on how much can do, ensures that the following will take place:
- provider is marked with an issue badge and excluded from being considered a candidate for performance improvements,
- reprobing is performed for destination prefixes routed through affected provider,
- outbound improvements through affected provider are withdrawn,
- max prepends are announced for inbound and transit prefixes through affected provider,
- FlowSpec rules to induce drop of BGP session towards affected provider are added,
Note that this is only possible if FlowSpec is enabled and the network is capable of processing FlowSpec rules. Dropping the BGP session with the affected provider causes all outbound and inbound traffic through this provider to be re-routed through known good providers.- affected provider is monitored to detect if the issue was temporary and if loss averages return to normal restore it to a good state.
Enable this feature for each of the designated provider as detailed in Figure Configuration editor: Add provider and review circuit issue detection thresholds as detailed in Figure Configuration editor: Circuit issues detection.
