Reduce public ip count

[TheSkorm]

AWS will be charging for public IPv4 addresses soon (https://aws.amazon.com/blogs/aws/new-aws-public-ipv4-address-charge-public-ip-insights/)

We currently use 6 IP addresses @ $0.005 per hour = ~$22 USD a month

Not mentioned in the article is LightSail, for we'll deal with that separately

Of these 6:

• 2x for ALB used for websockets, predictions and grafana
  • We might be able to switch this load balancer to V6 only and add a cloudfront distribution for each host header - special care will have to happen with websockets. Otherwise we can probably set this all to not cache
  • We will need to make sure users on v4 can access these endpoints via cloudfront
• 1x for Websocket main instance
• 1x for tawhiri
• 1x for grafana
• 1x for APRS gateway

The ECS services could likely switch to IPv6 using egress gateway. They don't permit direct traffic (or shouldn't anyway). The only tricky one is the APRS gateway, however I believe there is enough APRS-IS gateways that support IPv6 that this shouldn't be an issue.

[TheSkorm]

IPV6 public and private subnets created. Other subnets are now dualstack

[TheSkorm]

OpenSearch doesn't support IPv6 so unless we do something wild like proxy requests through CloudFront grafana will have to remain having a v4 address

[TheSkorm]

Can't do a lot until : aws/containers-roadmap#1340 and opensearch have IPv6 options

[TheSkorm]

OpenSearch now supports IPv6! https://aws.amazon.com/about-aws/whats-new/2023/10/amazon-opensearch-service-ipv6/