I have:

1. ExpressRoute connected via Equinix (status: "Enabled", "Provisioned")
2. Successful connection setup (Status: "Succeeded")
3. Successful Azure Private Peering setup (Status: )

However, there is this notice from the ExpressRoute Health Check:

 Degraded : At least 1 BGP session is down
At Monday, December 19, 2022 at 12:12:04 PM GMT 8, the Azure monitoring system received the following information regarding your ExpressRoute circuit:
The platform has detected that at least 1 BGP session on at least one peering on your circuit is currently down and may be causing degraded performance.

There is no circuit redundancy for the ER virtual circuit (we've opted to hang it all off one string!), however I'm sure there should still be a redundant BGP pair of BGP sessions over the single VC.

However, I cannot find any reference in the Azure Documentation to confirm this.

My questions are:

1. Should there be a redundant pair of BGP sessions, even over a single (non-redundant) ER connection for ExpressRoute?
2. Are both BGP sessions needed at all times or are they purely for redundancy?

CodePudding user response：

ER are HA by design.

NOTE : here you can see a circuit as GBP session (for more details :

For your point 2, from a pure network perspective, loosing one bgp session would not cause trouble. But you may pay attention to this message , specially if it is not the first time you see this happening, you will have to investigate.

NOTE (EQUINIX)

Please have a look at this document from Equinix regarding ER configuration Equinix Fabric

Hope this would help