Hello @Murarisetty Yamuna ,
Welcome to Microsoft Q&A Platform. Thank you for reaching out & hope you are doing well.
I understand that in your Express route circuit metrics, you found the following type of metrics: Arp Availability and BGP Availability showing 100% (Arp Availability (Avg)). And you would like to know what its impact on your Express Route Circuit is and how to identify when it reaches maximum threshold and get notified about this through alerts.
You can find all the ExpressRoute metrics listed in the below doc:
https://learn.microsoft.com/en-us/azure/expressroute/expressroute-monitoring-metrics-alerts
ARP Availability - Split by Peering:
You can view near to real-time availability of ARP (Layer-2 connectivity) across peerings and peers (Primary and Secondary ExpressRoute routers). This dashboard shows the Peering (for both Private and Microsoft) ARP session status across both peers.
- If it shows 100% for Private/Microsoft peering, it means the Private/Microsoft Peering ARP session status is up across both peers.
- If it shows 0% for Private/Microsoft peering, it means the Private/Microsoft Peering ARP session status is down for both peers.
This metric is split by peering meaning, you will see the metric for each peering type (Private/Microsoft).
BGP Availability - Split by Peer:
You can view near to real-time availability of BGP (Layer-3 connectivity) across peerings and peers (Primary and Secondary ExpressRoute routers). This dashboard shows the status for both Primary & Secondary BGP session status for each peering type.
- If it shows 100% for a session for a selected peering type, it means that particular BGP session status is up for the selected peering.
- If it shows 0% for a session for a selected peering type, it means that particular BGP session status is down for the selected peering.
This metric is split by peer meaning, you will see the metric for each BGP peer (Primary/Secondary router) in a selected peering type (Private/Microsoft).
To understand more about ARP and BGP, you can refer the below doc:
Azure Monitor alerts proactively notify you when important conditions are found in your monitoring data. They allow you to identify and address issues in your system before your customers notice them. You can set alerts on metrics, logs, and the activity log. Different types of alerts have benefits and drawbacks.
You can configure alerts for ARP availability down
and BGP availability down
referencing the below docs:
https://learn.microsoft.com/en-us/azure/expressroute/monitor-expressroute#alerts
https://learn.microsoft.com/en-us/azure/azure-monitor/alerts/alerts-types#metric-alerts
In addition to above, you can also configure alerts for Azure ExpressRoute circuit maintenance:
https://learn.microsoft.com/en-us/azure/expressroute/maintenance-alerts
Kindly let us know if the above helps or you need further assistance on this issue.
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