OSPF Peer Down Alert

The OSPF Peer Down alert is generated when an Open Shortest Path First (OSPF) neighbor adjacency transitions from an established state to a down state on a switch interface. This indicates that routing communication between OSPF peers has been interrupted.

A peer-down condition can affect route availability, trigger traffic rerouting, and impact network resiliency until adjacency is restored.

Figure 1: OSPF Peer Down Alert Sample

Alert Triggering and Clearing Conditions

  • Triggering Condition—The alert is triggered when an OSPF neighbor state changes to Down on an OSPF-enabled interface.

  • Clearing Condition—The alert automatically clears when the OSPF adjacency is successfully re-established and the neighbor returns to an operational state.

Common Causes

Queue drops may occur due to the following reasons:

  • Interface state or status is down on the OSPF link.

  • Hello timer mismatch between OSPF neighbors.

  • Dead timer mismatch preventing adjacency formation.

  • Duplicate Router ID detected in the OSPF domain.

  • Authentication failure due to mismatched credentials.

  • Authentication type mismatch between peers.

Alert Behavior

When an OSPF Peer Down alert is triggered:

  • Classic Central detects the loss of OSPF adjacency and flags the affected switch and interface.

  • The alert is integrated with Switch Health for routing visibility. The affected neighbor, interface, and routing context are displayed in the alert view.

  • Diagnostic insights and remediation guidance are available in the Action section.

  • Summary Card

    The Summary card provides a concise overview of the alert, including:

    • Affected switch, interface, and OSPF neighbor.

    • Neighbor IP address and routing context.

    • Alert priority level.

    • First occurred, last occurred, and duration.

    • Number of occurrences.

    • Firmware version and alert scope Basic interface properties.

  • Impact Card

    The Impact section indicates whether the event affects: Switches, access points, clients, and network services.

  • Troubleshooting Card

    Provides a quick diagnostic summary for the OSPF Peer Down alert. Displays troubleshoot test reference and overall test status (Passed or Failed). Highlights high-level issues related to OSPF adjacency, configuration, or interface state. Allows access to detailed diagnostics through the expand icon.

    • ORCA View (Expanded Diagnostics)

      Click the expand icon in the Troubleshooting card to view the ORCA tab. The ORCA provides detailed automated root cause analysis for the affected OSPF neighbor and interface. It highlights the primary issue affecting OSPF adjacency. Indicates troubleshoot status and detects issues such as dead timer mismatch, hello timer mismatch, or configuration inconsistencies.

Recommended Actions

When you receive a OSPF Peer Down alert:

  • Verify that the OSPF interface is up and operational on both peers.

  • Ensure hello and dead timers match between neighbors.

  • Check for duplicate router IDs in the OSPF domain.

  • Confirm authentication type and keys match on both devices.

  • Validate IP addressing and subnet configuration.

  • Check for MTU mismatches between neighbors.

  • Review recent configuration changes affecting routing.

  • Monitor adjacency status to confirm successful recovery.

Related Events

The alert is associated with OSPF neighbor state change events and routing adjacency loss notifications.

Additional Notes

OSPF Peer Down alerts are generated per neighbor adjacency. Alerts automatically clear once adjacency is restored. Frequent adjacency drops may indicate routing instability and should be investigated promptly.