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Need second CIDR block for AWS VPC

I have a CIDR block of 172.25.0.0/16 and need to create a second one for a new vpc I need to create. I do not want the CIDR to overlap. Can someone help in identifying which I can use?

  • Then for that I also need 2 private subnets.. then 2 public subnets.
Solution

  • AWS recommends using CIDRs from the following ranges:

    10.0.0.0 - 10.255.255.255 (10/8 prefix) Your VPC must be /16 or smaller, for example, 10.0.0.0/16.

    172.16.0.0 - 172.31.255.255 (172.16/12 prefix) Your VPC must be /16 or smaller, for example, 172.31.0.0/16.

    192.168.0.0 - 192.168.255.255 (192.168/16 prefix) Your VPC can be smaller, for example 192.168.0.0/20.

    Since you area already using 172.25.0.0/16 you can choose 172.30.0.0/16, 10.0.0.0/16 or whatever you want from these ranges.