I'm testing some cloudformation infrastructure templates, and I noticed that most of the examples include routing tables to connect private subnets to public subnets, but my question then is:
if two private subnets exist in different AZs (and are attached to individual routing tables) and the resources within them may need to access a resource on the other subnet (for example a private service on the subnet 1 accessing a database on the subnet 2)
- Should I create a route to connect the two private subnets in each of their routing tables?
- Would it be a better practice to attach both subnets to a single shared routing table (both CIDRs are contiguous)?