Kentik is happy to announce new support for AWS Transit Gateway (TGW) flow logs.

Many customers prefer to rely on TGW flow logs instead of VPC flow logs as the primary source of traffic information about their AWS environments.

A Transit Gateway typically interconnects different VPCs and other gateways (Direct Connect, VPNs, etc.) In this case, the TGW sits at a central point of a customer’s AWS network, observing all the traffic passing through, and can serve as a single flow log generation point. For many customers, that should reduce the cost of flow log generation, and allow for analysis and detection of performance-impacting issues that span multiple environments.

Previous Kentik Cloud releases required customers to enable flow logs at the VPC level for every monitored VPC. That often led to duplication of flow data, as one flow can be observed across many VPCs, generating the same flow record in each. Since AWS charges customers for the volume of the flow records generated, this added unnecessary cost.

Some VPCs may still require enablement of flow log generation at the VPC level to see traffic that may not go through the TGW; for example, when VPC-to-VPC peering is configured, or when Direct Connect or VPN terminates inside the VPC rather than a TGW.

Please contact your CSE or account team with any questions you have.