Troubleshooting BGP Connections

Use the BGP page to review your BGP connections and settings. To open this page, in your Aviatrix Controller, go to MULTI-CLOUD TRANSIT > BGP on the left sidebar.

BGP Page: Connections Tab

If you set up a Transit Network, the Transit gateways will be listed on the BGP page in the Connections tab.

You can view which Transit gateway carries the network traffic from a specific Spoke VPC/VNet.

Select one Transit gateway to view its details.

  • Advertised Networks represents the list of Spoke GW CIDR list. If the list of the Advertised Networks includes the Spoke VPC/VNet CIDR, the Transit gateway routes traffic from the Spoke to on-prem; if it does not, check the backup Transit gateway.

  • Learned routes represents the list of on-prem network CIDRs propagated by VGW.

  • Local AS Num is the Transit gateway AS number you specified at the time of Step 3 when connecting to VGW.

BGP Page: Diagnostics Tab

Use the Diagnostics tab on the BGP page to troubleshoot BGP problems. Aviatrix BGP is implemented by using Quagga.

You can either type in Quagga commands or select Predefined Show List for a list of pre-defined BGP commands.

If you turn on debug command, make sure to turn it off when debug is finished to ensure the Transit Gateway is not flooded with debug messages. Excessive debug messages reduce throughput.

To troubleshoot connectivity between a Spoke VPC/VNet instance and an on-prem host, see Troubleshooting Spoke VPC/VNet and On-Prem Connection.

BGP Page: Configuration Tab

Use the Configuration tab on the BGP page to edit your BGP settings if necessary.

BGP Overlapping Alert Email

When the Aviatrix Controller detects that on-prem propagated routes overlap or are a superset of Spoke VPC/VNet CIDR ranges, it sends an email to an administrator, alerting a potential misconfiguration. Such email is sent once when a route change event occurs, for example, when BGP routes are flapping.

This feature is enabled by default. If you wish not to receive the alert email, you can disable it.

Go to Multi-Cloud Transit > BGP > Configuration and find the BGP Overlapping Alert Email setting. Click on the toggle switch to change the status to Disabled.

BGP Route Limit Alert Email

AWS VGW BGP supports up to 100 routes. When this limit is reached, VGW BGP goes down and causes outage. This email alert notifies admin when routes approach 90.

BGP Maximum AS Limits

The BGP Maximum AS Limit sets the maxium number of BGP hops the Controller allows the route to propagate. This limit determines the scope of a BGP network by setting the maxium BGP AS path length.

This setting is disabled by default, meaning that the network size is unlimited.

If you wish to limit the size of your network (for example, if you have a complex topology between your on-prem and cloud networks), you can enable this option by entering 1-254 in the field provided. Then, use the up and down arrows to increase or decrease the number.