How to propagate additional newly added route in route table

Question

Hi All,

I am running a site-to-site VPC and my home subnet can talk to private subnet on AWS. 
Now I want to add another home subnet, to do that I added a new route in route table and associated the same VPN gateway however the route propogation tab is not changing to "Yes" for this new route. Please see the stable below, it is 192.168.100.0/24 subnet that I need to be propagated.  Appreciate your suggestions.

```

172.16.0.0/20	local	Active	No
192.168.1.0/24	vgw-00af09ab915d4356b	Active	Yes
192.168.100.0/24	vgw-00af09ab915d4356b	Active	No
```

Accepted Answer

A route entry can either be propagated or statically added to the route table (like you did here). It can't be both.

I suggest you do the following:

1. Remove the static route you added to your route table.
2. Navigate to: VPC -> Site-to-Site VPN connections -> Select you VPN ID -> Static routes -> Add all the relevant routes of your home subnets here (in your example 192.168.1.0/24 & 192.168.100.0/24)
3. Navigate to: VPC -> Route tables -> select the route table ID associated with your subnet -> Route propagation -> Edit route propagation -> Tick the "Enable" Propagation checkbox. (repeat for all relevant route tables)

This will take care to automatically propagate new routes that you add to your VPN to all the route tables that have the propagation enabled.

How to propagate additional newly added route in route table

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