continued progress on infra docs

docs/63_dandi_infrastructure.md

@@ -1,15 +1,5 @@
 # Work In Progress
 
-## Understanding the DANDI Infrastructure
-
-### Girder
-
-### AWS Buckets
-
-### Domain Management
-
-### Staging vs. Production
-
 ## Configuring Terraform
 
 [First, make sure you have properly set up your Terraform Cloud account and linked the account to the proper GitHub repository](../60_initialize_vendors/#terraform-cloud)
@@ -56,10 +46,67 @@ alt="terraform_manual"
 style="width: 60%; height: auto; display: block; margin-left: auto;  margin-right: auto;"/>
 <br/><br/>
 
-## Manual Steps in the AWS Console and Netlify
+## Understanding the DANDI Infrastructure
+
+### Girder
+
+In the [api.tf definition](https://github.com/dandi/dandi-infrastructure/blob/master/terraform/api.tf), there is reference
+to a `source` keyword, where a [Terraform module called girder is defined](https://github.com/girder/terraform-heroku-girder4).
+
+In the Girder submodule, AWS and Heroku resources are defined that facilitate base resources for compute and networking to work with DANDI Archive.
+
+Within the DANDI Infrastructure downstream, Girder is used by declaring values that the Terraform module expects. **Resources declared by Girder cannot be overwritten**
+
+#### Sponsored Bucket
+
+**This is DANDI Archive specific** in which the code in `main.tf` and the presence of downstream-related files should be commented out for any clones.
+
+A `sponsored bucket` is also declared in the `main.tf`, with downstream, related files called `sponsored_iam.tf` and `sponsored_bucket.tf`.
 
+## Domain Management
 
+DANDI Infrastructure manages domains for two different vendors:
+- `Netlify`: Manages load balancer IPs, as well as custom domains, specifically for the UI
+- `AWS Route 53`: Manages all API-based endpoints, as well as email and SSL certificate domains
 
-## Setting up Email
+### Netlify
 
-TBD
+Although Netlify prescribes mapping of Netlify-issued DNS records directly, DANDI Infrastructure relies on mapping Netlify's Load Balancer IP to the respective A Name Record in AWS Route 53, 
+as prescribed in [Netlify's docs here](https://docs.netlify.com/domains-https/custom-domains/configure-external-dns/#configure-an-apex-domain)
+
+```
+resource "aws_route53_record" "gui" {
+  zone_id = aws_route53_zone.dandi.zone_id
+  name    = "" # apex
+  type    = "A"
+  ttl     = "300"
+  records = ["75.2.60.5"] # Netlify's load balancer, which will proxy to our app
+}
+```
+
+Note the code blob above, as referenced from [DANDI Infrastructure domain.tf Terraform template](https://github.com/dandi/dandi-infrastructure/blob/master/terraform/domain.tf#L13).
+
+### AWS Route 53
+
+## AWS Buckets
+
+While [Girder](https://github.com/girder/terraform-heroku-girder4) does declare S3-based resources, configuration is still needed within DANDI Infrastructure.
+
+Find your AWS Account ID. This value will be referenced in the `main.tf` Terraform template
+
+<br/><br/>
+<img
+src="../img/aws_account.png"
+alt="aws_account"
+style="width: 60%; height: auto; display: block; margin-left: auto;  margin-right: auto;"/>
+<br/><br/>
+
+Populate the value in the [appropriate account ID reference](https://github.com/dandi/dandi-infrastructure/blob/master/terraform/main.tf#L14) in the `main.tf` template.
+
+### Staging vs. Production
+
+### Email Setup
+
+TBD
+
+## Manual Steps in the AWS Console and Netlify