Problem Statement
Avaya Communication Manager reports a Minor cmgH248LinkDown alarm indicating that the H.248 link between a Media Gateway and its controller is down.
Impact
The affected Media Gateway may be unable to provide voice services for endpoints, trunks, or resources homed to that gateway until the H.248 link is restored. Other gateways with H.248 links up should continue operating normally.
Alarm
cmgH248LinkDown
Troubleshooting Steps
- Confirm the alarm details in the monitoring dashboard, including severity, maintenance object, alarm code, and affected equipment number or Media Gateway identifier.
- Access Avaya Communication Manager using an authorized administrative session.
- Run `status media-gateways` to review the H.248 Link Summary and identify which Media Gateway shows `dn` under link status.
- Compare the affected Media Gateway in Communication Manager with the equipment number from the alarm to ensure the correct gateway is being investigated.
- If the gateway link is down, verify site-side conditions for the affected Media Gateway, including power, physical network connectivity, and any local LAN/WAN outage indicators.
- Verify network reachability between the Media Gateway and the Communication Manager/controller using approved network tools and standard operational procedures.
- Check for related Communication Manager alarms that may indicate broader connectivity, controller, or gateway issues.
- If the gateway has recovered, rerun `status media-gateways` and confirm the affected Media Gateway link shows `up`.
- Continue monitoring until the dashboard alarm clears or is no longer active.
Resolution
The alarm can be resolved when the affected Media Gateway H.248 link returns to `up` status and the active cmgH248LinkDown alarm clears from monitoring. In the referenced event, the gateway was confirmed back up and the alarm was closed after verification.