Example of routing configuation¶
Imported from Confluence
Content may be outdated. Verify before following any procedures. View original | Last updated: May 2023
Why¶
Given the number of hops in our AWS ↔ GCP cloud-to-cloud, it's pretty easy to run into a problem when one of the routing tables is forgotten to be updated.
This article describes real steps taken when setting a connection between a VM in GCP subnet and AWS FairBid RDS/EKS.
Requirements¶
From a subnet in GCP: 10.189.5.0/24 → to a subnet in AWS: 172.30.0.2/32 (subnet-growth-prod-useast1-vm).
Hops¶
- Hop #1 - in AWS: update gateway associations with 172.30.0.2/32
AWS Direct Connect -> Transit gateways -> TGW-0A54FE1C5DD929383 -> Gateway associations -> 8BC487BE-9FBB-418B-9741-0CD8213B0C48 -> Edit association -> Add 172.30.0.2/32
- Hop #2 - in AWS: to the routing tables associated with 172.30.0.2/32 subnet adding Transit Gateway endpoint for GCP CIDR (10.189.5.0/24)
FOR:
rtb-0186c3672bceb025d / bln-private-subnet-us-east-1b
rtb-0ff664472b327584b / bln-private-subnet-us-east-1c
rtb-02e71e825aef5d513 / bln-private-subnet-us-east-1d
ROUTE:
10.189.5.0/24 -> tgw-0a54fe1c5dd929383
- Hop #3 - in Packet Fabric: append 10.189.5.0/24 and 172.30.0.2/32 to the route tables associated with all connection between GCP and AWS
Info
Note that depending on the direction of the connections in the packet fabric each CIDR have to be mentioned 2 times in targets list and 2 times in sources list.
Packer fabric connections:
GCP WDC1 to AWS WDC1
AWS WDC1 to GCP WDC1
AWS WDC2 to GCP WDC2
GCP WDC2 to AWS WDC2
- Hop #4 - in GCP Transit Project (agp-transit-network-prod-lw): add 10.189.5.0/24 to both BGP sessions of the cloud router
- Hop #5 - in GCP Transit Project (agp-transit-network-prod-lw): add 172.30.0.2/32 to both BGP sessions of the cloud router