vlt/SwD/cidrs.md

issues

• the big one, you can't actually edit the CIDR of a VPC in AWS

  • the whole concept is it's difficult to migrate resources in the case of
    • CIDR conflict
      • we hit a cidr conflict with ENDE anyway lol
    • vpc peering
    • onprem etc
  • so while you could make a new vpc there's a big migration effort in moving everything into that new VPC

• 10.x.x.x for ap-southeast-2

  • we only use 10.0.x.x
  • soooooo that's effectively 1/255 available to us

• msk recreated on subnet change

• upcoming

  • ende scaling up
  • 100k load test
  • hp will initially be 4x the size of ende

potential layout

swdutsrsvdev 10.4.0.0/8 10.4.0.0 10.4.255.255

msk                     10.4.16.0/21                10.4.16.0   10.4.23.255
    ap-southeast-2a     10.4.16.0/24 
    ap-southeast-2b     10.4.17.0/24 
    ap-southeast-2c     10.4.18.0/24

    -- oh shit too small --
    -- msk needs to be replaced when changing subnets --
    -- create new msk with --
    ap-southeast-2a     10.4.19.0/24 
    ap-southeast-2b     10.4.20.0/24 
    ap-southeast-2c     10.4.21.0/24
    ap-southeast-2a     10.4.21.0/24 
    ap-southeast-2b     10.4.22.0/24 
    ap-southeast-2c     10.4.23.0/24

    -- still got it wrong --
    -- create new msk in different block --
    -- old block becomes free again --
    ap-southeast-2a     10.4.32.0/24
    ap-southeast-2b     10.4.33.0/24
    ...



elasticache             10.4.24.0/21                10.4.24.0   10.4.31.255
    ap-southeast-2a     10.4.24.0/24 
    ap-southeast-2b     10.4.25.0/24 
    ap-southeast-2c     10.4.26.0/24

gsf                     10.4.128.0/19               10.4.128.0  10.4.191.255
    ap-southeast-2a         10.4.128.0 
    ap-southeast-2b         10.4.129.0
    ap-southeast-2c         10.4.130.0