You'll need to be logged in as an Admin or Manager of your Cloud Connector to edit route summarisation.
Route summarisation gives you the ability to limit the number of routes advertised into your AWS VPC on your virtual private interface. Your options are listed under route summarisation definitions.
If you advertise more than 100 routes to AWS, AWS will drop your BGP sessions and your connection to AWS will be down until the number of advertised routes is reduced below 100. This limit is imposed by AWS.
Of the four options listed below, the risk of outage are:
- RFC1918 drop public – no risk
- RFC1918 allow public – low risk
- Default route summarisation – no risk
- No route summarisation – medium to high risk as no restrictions are imposed on routing table size.
Route summarisation definitions
This is the recommended option.
The Telstra Next IP network service RFC1918 Route Summarisation consolidates all private
You're free to use RFC 1918 address space inside your Amazon VPC. RFC1918 Route Summarisation is only performed in the outbound direction (from your Telstra Next IP network service in the direction of your AWS cloud services). Subsets of these RFC1918 ranges can still be configured in AWS and advertised into your Telstra IP network service VPN.
When you choose this option any Next IP routes that don't fall within the RFC 1918 ranges will be dropped and only the three RFC1918 summary routes will be advertised to AWS from your Telstra network. This option is suitable if you have large numbers of both private and public routes in your Telstra IP network.
Choosing this option will also suppress the default route (0.0.0.0/0) from being advertised from your Telstra IP network service to your AWS cloud services. This will allow you to use the AWS internet gateway for internet bound traffic from your AWS cloud services while also routing traffic destined for your Telstra IP network service via your AWS Virtual Private Interface.
This is the configuration we recommend for establishing BGP peering to your AWS VPC (if you primarily use RFC1918 addressing within your Telstra IP network service).
|RFC1918 allow public
As above, except routes that don't fall into the RFC1918 ranges are not summarised and will be advertised into your Virtual Private Cloud (VPC) without change.
If you have more than 97 routes that are non-RFC1918 VPN routes, then BGP peering will not establish to your AWS VPC. The 100 route limit is imposed by AWS.
|Default route summarisation
Only advertises a default route from your Telstra IP network service to your AWS VPC, so all traffic from your VPC will be routed back into your VPN. Please refer to documentation on AWS’ route tables if you intend on using the AWS internet gateway in conjunction with this option.
If you wish to advertise a default route (0.0.0.0/0) from your Telstra IP network service into your AWS cloud services, then it’s best to choose this option.
|No route summarisation
This option is not recommended as it has a high chance of an outage occurring.
No route summarisation is performed and all routes from your VPN will be advertised into your VPC. Only choose this if you are sure that there are less than 100 routes in your VPN.